56643660 has 144 divisors (see below), whose sum is σ = 184687776. Its totient is φ = 14002176.

The previous prime is 56643659. The next prime is 56643661. The reversal of 56643660 is 6634665.

56643660 is a `hidden beast` number, since 5 + 6 + 643 + 6 + 6 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (56643659) and next prime (56643661).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56643661) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 327334 + ... + 327506.

It is an arithmetic number, because the mean of its divisors is an integer number (1282554).

Almost surely, 2^56643660 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 56643660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (92343888).

56643660 is an abundant number, since it is smaller than the sum of its proper divisors (128044116).

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

56643660 is a wasteful number, since it uses less digits than its factorization.

56643660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 312 (or 307 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 36.

The square root of 56643660 is about 7526.1982434693. The cubic root of 56643660 is about 384.0464624770.

The spelling of 56643660 in words is "fifty-six million, six hundred forty-three thousand, six hundred sixty".