56131075621 has 4 divisors (see below), whose sum is σ = 56131795692. Its totient is φ = 56130355552.

The previous prime is 56131075579. The next prime is 56131075667. The reversal of 56131075621 is 12657013165.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12657013165 = 5 ⋅2531402633.

It can be written as a sum of positive squares in 2 ways, for example, as 14942373121 + 41188702500 = 122239^2 + 202950^2 .

It is a cyclic number.

It is not a de Polignac number, because 56131075621 - 2¹³ = 56131067429 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56131075681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 226630 + ... + 404503.

It is an arithmetic number, because the mean of its divisors is an integer number (14032948923).

Almost surely, 2^56131075621 is an apocalyptic number.

It is an amenable number.

56131075621 is a deficient number, since it is larger than the sum of its proper divisors (720071).

56131075621 is an equidigital number, since it uses as much as digits as its factorization.

56131075621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 720070.

The product of its (nonzero) digits is 37800, while the sum is 37.

Adding to 56131075621 its reverse (12657013165), we get a palindrome (68788088786).

The spelling of 56131075621 in words is "fifty-six billion, one hundred thirty-one million, seventy-five thousand, six hundred twenty-one".