56000991 has 4 divisors (see below), whose sum is σ = 74667992. Its totient is φ = 37333992.

The previous prime is 56000969. The next prime is 56001041. The reversal of 56000991 is 19900065.

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

It is not a de Polignac number, because 56000991 - 2⁶ = 56000927 is a prime.

It is a super-2 number, since 2×56000991² = 6272221985964162, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56000951) 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, 9333496 + ... + 9333501.

It is an arithmetic number, because the mean of its divisors is an integer number (18666998).

Almost surely, 2^56000991 is an apocalyptic number.

56000991 is a deficient number, since it is larger than the sum of its proper divisors (18667001).

56000991 is a wasteful number, since it uses less digits than its factorization.

56000991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18667000.

The product of its (nonzero) digits is 2430, while the sum is 30.

The square root of 56000991 is about 7483.3809872276. The cubic root of 56000991 is about 382.5884933445.

The spelling of 56000991 in words is "fifty-six million, nine hundred ninety-one", and thus it is an aban number.