56781913 has 4 divisors (see below), whose sum is σ = 58739940. Its totient is φ = 54823888.

The previous prime is 56781841. The next prime is 56781919. The reversal of 56781913 is 31918765.

56781913 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in 2 ways, for example, as 18688329 + 38093584 = 4323^2 + 6172^2 .

It is a cyclic number.

It is not a de Polignac number, because 56781913 - 2¹³ = 56773721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (56781919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 978970 + ... + 979027.

It is an arithmetic number, because the mean of its divisors is an integer number (14684985).

Almost surely, 2^56781913 is an apocalyptic number.

It is an amenable number.

56781913 is a deficient number, since it is larger than the sum of its proper divisors (1958027).

56781913 is a wasteful number, since it uses less digits than its factorization.

56781913 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1958026.

The product of its digits is 45360, while the sum is 40.

The square root of 56781913 is about 7535.3774291670. The cubic root of 56781913 is about 384.3586623853.

The spelling of 56781913 in words is "fifty-six million, seven hundred eighty-one thousand, nine hundred thirteen".