56621612665 has 4 divisors (see below), whose sum is σ = 67945935204. Its totient is φ = 45297290128.

The previous prime is 56621612653. The next prime is 56621612711.

56621612665 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 21979841536 + 34641771129 = 148256^2 + 186123^2 .

It is a cyclic number.

It is not a de Polignac number, because 56621612665 - 2⁹ = 56621612153 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5662161262 + ... + 5662161271.

It is an arithmetic number, because the mean of its divisors is an integer number (16986483801).

Almost surely, 2^56621612665 is an apocalyptic number.

It is an amenable number.

56621612665 is a deficient number, since it is larger than the sum of its proper divisors (11324322539).

56621612665 is a wasteful number, since it uses less digits than its factorization.

56621612665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11324322538.

The product of its digits is 777600, while the sum is 46.

The spelling of 56621612665 in words is "fifty-six billion, six hundred twenty-one million, six hundred twelve thousand, six hundred sixty-five".