56155561 has 8 divisors (see below), whose sum is σ = 70012224. Its totient is φ = 43757520.

The previous prime is 56155543. The next prime is 56155591. The reversal of 56155561 is 16555165.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 56155561 - 2¹⁷ = 56024489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (56155511) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 364570 + ... + 364723.

It is an arithmetic number, because the mean of its divisors is an integer number (8751528).

Almost surely, 2^56155561 is an apocalyptic number.

It is an amenable number.

56155561 is a deficient number, since it is larger than the sum of its proper divisors (13856663).

56155561 is a wasteful number, since it uses less digits than its factorization.

56155561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 729311.

The product of its digits is 22500, while the sum is 34.

The square root of 56155561 is about 7493.7014218609. The cubic root of 56155561 is about 382.9401679447.

The spelling of 56155561 in words is "fifty-six million, one hundred fifty-five thousand, five hundred sixty-one".