56561664 has 52 divisors (see below), whose sum is σ = 150845456. Its totient is φ = 18849792.

The previous prime is 56561663. The next prime is 56561677. The reversal of 56561664 is 46616565.

It is not an unprimeable number, because it can be changed into a prime (56561663) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9987 + ... + 14589.

Almost surely, 2^56561664 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 56561664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (75422728).

56561664 is an abundant number, since it is smaller than the sum of its proper divisors (94283792).

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

56561664 is an equidigital number, since it uses as much as digits as its factorization.

56561664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4630 (or 4608 counting only the distinct ones).

The product of its digits is 129600, while the sum is 39.

The square root of 56561664 is about 7520.7488988797. The cubic root of 56561664 is about 383.8610608461.

The spelling of 56561664 in words is "fifty-six million, five hundred sixty-one thousand, six hundred sixty-four".