56904781 has 4 divisors (see below), whose sum is σ = 58228192. Its totient is φ = 55581372.

The previous prime is 56904773. The next prime is 56904787. The reversal of 56904781 is 18740965.

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: 18740965 = 5 ⋅3748193.

It is a cyclic number.

It is not a de Polignac number, because 56904781 - 2³ = 56904773 is a prime.

It is a super-2 number, since 2×56904781² = 6476308201315922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56904787) 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, 661641 + ... + 661726.

It is an arithmetic number, because the mean of its divisors is an integer number (14557048).

Almost surely, 2^56904781 is an apocalyptic number.

It is an amenable number.

56904781 is a deficient number, since it is larger than the sum of its proper divisors (1323411).

56904781 is a wasteful number, since it uses less digits than its factorization.

56904781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1323410.

The product of its (nonzero) digits is 60480, while the sum is 40.

The square root of 56904781 is about 7543.5257671728. The cubic root of 56904781 is about 384.6356951910.

The spelling of 56904781 in words is "fifty-six million, nine hundred four thousand, seven hundred eighty-one".