3645391680 has 672 divisors, whose sum is σ = 15621365760. Its totient is φ = 761425920.

The previous prime is 3645391679. The next prime is 3645391681. The reversal of 3645391680 is 861935463.

3645391680 is a `hidden beast` number, since 36 + 4 + 539 + 1 + 6 + 80 = 666.

It is an interprime number because it is at equal distance from previous prime (3645391679) and next prime (3645391681).

It is a tau number, because it is divible by the number of its divisors (672).

It is a super-2 number, since 2×3645391680² = 26577761001226444800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3645391681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 11874087 + ... + 11874393.

It is an arithmetic number, because the mean of its divisors is an integer number (23246080).

Almost surely, 2^3645391680 is an apocalyptic number.

3645391680 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3645391680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7810682880).

3645391680 is an abundant number, since it is smaller than the sum of its proper divisors (11975974080).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

3645391680 is a wasteful number, since it uses less digits than its factorization.

3645391680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 387 (or 374 counting only the distinct ones).

The product of its (nonzero) digits is 466560, while the sum is 45.

The square root of 3645391680 is about 60377.0790946366. The cubic root of 3645391680 is about 1539.0334745926.

The spelling of 3645391680 in words is "three billion, six hundred forty-five million, three hundred ninety-one thousand, six hundred eighty".