1800643680 has 576 divisors, whose sum is σ = 7321466880. Its totient is φ = 398131200.

The previous prime is 1800643667. The next prime is 1800643721. The reversal of 1800643680 is 863460081.

It is a happy number.

1800643680 is a `hidden beast` number, since 1 + 8 + 0 + 0 + 643 + 6 + 8 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 9329664 + ... + 9329856.

It is an arithmetic number, because the mean of its divisors is an integer number (12710880).

Almost surely, 2^1800643680 is an apocalyptic number.

1800643680 is a gapful number since it is divisible by the number (10) 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 1800643680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3660733440).

1800643680 is an abundant number, since it is smaller than the sum of its proper divisors (5520823200).

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

1800643680 is a wasteful number, since it uses less digits than its factorization.

1800643680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 275 (or 264 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The square root of 1800643680 is about 42433.9920346884. The cubic root of 1800643680 is about 1216.5853815297.

The spelling of 1800643680 in words is "one billion, eight hundred million, six hundred forty-three thousand, six hundred eighty".