56720277015557 has 2 divisors, whose sum is σ = 56720277015558. Its totient is φ = 56720277015556.

The previous prime is 56720277015503. The next prime is 56720277015637. The reversal of 56720277015557 is 75551077202765.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 56513798564356 + 206478451201 = 7517566^2 + 454399^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-56720277015557 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 56720277015496 and 56720277015505.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (56720277011557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28360138507778 + 28360138507779.

It is an arithmetic number, because the mean of its divisors is an integer number (28360138507779).

Almost surely, 2^{56720277015557} is an apocalyptic number.

It is an amenable number.

56720277015557 is a deficient number, since it is larger than the sum of its proper divisors (1).

56720277015557 is an equidigital number, since it uses as much as digits as its factorization.

56720277015557 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36015000, while the sum is 59.

The spelling of 56720277015557 in words is "fifty-six trillion, seven hundred twenty billion, two hundred seventy-seven million, fifteen thousand, five hundred fifty-seven".