645888546 has 64 divisors (see below), whose sum is σ = 1518000000. Its totient is φ = 203000256.

The previous prime is 645888533. The next prime is 645888559.

645888546 is a `hidden beast` number, since 6 + 4 + 588 + 8 + 54 + 6 = 666.

645888546 is nontrivially palindromic in base 10.

It is an interprime number because it is at equal distance from previous prime (645888533) and next prime (645888559).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a junction number, because it is equal to n+sod(n) for n = 645888492 and 645888501.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 233580 + ... + 236328.

It is an arithmetic number, because the mean of its divisors is an integer number (23718750).

Almost surely, 2^645888546 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 645888546, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (759000000).

645888546 is an abundant number, since it is smaller than the sum of its proper divisors (872111454).

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

645888546 is a wasteful number, since it uses less digits than its factorization.

645888546 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3008 (or 3002 counting only the distinct ones).

The product of its digits is 7372800, while the sum is 54.

The square root of 645888546 is about 25414.3374102100. The cubic root of 645888546 is about 864.4088294739.

The spelling of 645888546 in words is "six hundred forty-five million, eight hundred eighty-eight thousand, five hundred forty-six".