56387691 has 16 divisors (see below), whose sum is σ = 88452000. Its totient is φ = 35380224.

The previous prime is 56387689. The next prime is 56387699. The reversal of 56387691 is 19678365.

It is a happy number.

56387691 is a `hidden beast` number, since 5 + 638 + 7 + 6 + 9 + 1 = 666.

It is not a de Polignac number, because 56387691 - 2¹ = 56387689 is a prime.

It is a super-2 number, since 2×56387691² = 6359143392622962, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (56387699) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 60966 + ... + 61883.

It is an arithmetic number, because the mean of its divisors is an integer number (5528250).

Almost surely, 2^56387691 is an apocalyptic number.

56387691 is a gapful number since it is divisible by the number (51) formed by its first and last digit.

56387691 is a deficient number, since it is larger than the sum of its proper divisors (32064309).

56387691 is a wasteful number, since it uses less digits than its factorization.

56387691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122875 (or 122869 counting only the distinct ones).

The product of its digits is 272160, while the sum is 45.

The square root of 56387691 is about 7509.1737894392. The cubic root of 56387691 is about 383.4670952641.

The spelling of 56387691 in words is "fifty-six million, three hundred eighty-seven thousand, six hundred ninety-one".