56661637 has 4 divisors (see below), whose sum is σ = 56811520. Its totient is φ = 56511756.

The previous prime is 56661617. The next prime is 56661641. The reversal of 56661637 is 73616665.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 73616665 = 5 ⋅14723333.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-56661637 is a prime.

It is a super-2 number, since 2×56661637² = 6421082215039538, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 56661637.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56661607) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 74373 + ... + 75130.

It is an arithmetic number, because the mean of its divisors is an integer number (14202880).

Almost surely, 2^56661637 is an apocalyptic number.

It is an amenable number.

56661637 is a deficient number, since it is larger than the sum of its proper divisors (149883).

56661637 is a wasteful number, since it uses less digits than its factorization.

56661637 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149882.

The product of its digits is 136080, while the sum is 40.

The square root of 56661637 is about 7527.3924436022. The cubic root of 56661637 is about 384.0870864586.

The spelling of 56661637 in words is "fifty-six million, six hundred sixty-one thousand, six hundred thirty-seven".