56159781 has 8 divisors (see below), whose sum is σ = 75469824. Its totient is φ = 37144800.

The previous prime is 56159771. The next prime is 56159797. The reversal of 56159781 is 18795165.

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

It is not a de Polignac number, because 56159781 - 2⁵ = 56159749 is a prime.

It is a super-2 number, since 2×56159781² = 6307842003935922, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56159771) 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, 73320 + ... + 74081.

It is an arithmetic number, because the mean of its divisors is an integer number (9433728).

Almost surely, 2^56159781 is an apocalyptic number.

It is an amenable number.

56159781 is a deficient number, since it is larger than the sum of its proper divisors (19310043).

56159781 is a wasteful number, since it uses less digits than its factorization.

56159781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147531.

The product of its digits is 75600, while the sum is 42.

The square root of 56159781 is about 7493.9829863698. The cubic root of 56159781 is about 382.9497601502.

The spelling of 56159781 in words is "fifty-six million, one hundred fifty-nine thousand, seven hundred eighty-one".