56155463981 has 2 divisors, whose sum is σ = 56155463982. Its totient is φ = 56155463980.

The previous prime is 56155463977. The next prime is 56155464031. The reversal of 56155463981 is 18936455165.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 54639062500 + 1516401481 = 233750^2 + 38941^2 .

It is a cyclic number.

It is not a de Polignac number, because 56155463981 - 2² = 56155463977 is a prime.

It is a super-2 number, since 2×56155463981² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (56155463971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28077731990 + 28077731991.

It is an arithmetic number, because the mean of its divisors is an integer number (28077731991).

Almost surely, 2^56155463981 is an apocalyptic number.

It is an amenable number.

56155463981 is a deficient number, since it is larger than the sum of its proper divisors (1).

56155463981 is an equidigital number, since it uses as much as digits as its factorization.

56155463981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3888000, while the sum is 53.

The spelling of 56155463981 in words is "fifty-six billion, one hundred fifty-five million, four hundred sixty-three thousand, nine hundred eighty-one".