56205661 has 4 divisors (see below), whose sum is σ = 56230912. Its totient is φ = 56180412.

The previous prime is 56205649. The next prime is 56205679. The reversal of 56205661 is 16650265.

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: 16650265 = 5 ⋅3330053.

It is a cyclic number.

It is not a de Polignac number, because 56205661 - 2⁷ = 56205533 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56205641) 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, 8925 + ... + 13858.

It is an arithmetic number, because the mean of its divisors is an integer number (14057728).

Almost surely, 2^56205661 is an apocalyptic number.

It is an amenable number.

56205661 is a deficient number, since it is larger than the sum of its proper divisors (25251).

56205661 is a wasteful number, since it uses less digits than its factorization.

56205661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25250.

The product of its (nonzero) digits is 10800, while the sum is 31.

The square root of 56205661 is about 7497.0434839342. The cubic root of 56205661 is about 383.0540159734.

The spelling of 56205661 in words is "fifty-six million, two hundred five thousand, six hundred sixty-one".