56420626781 has 4 divisors (see below), whose sum is σ = 56454433500. Its totient is φ = 56386820064.

The previous prime is 56420626777. The next prime is 56420626793. The reversal of 56420626781 is 18762602465.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18762602465 = 5 ⋅3752520493.

It can be written as a sum of positive squares in 2 ways, for example, as 28786551556 + 27634075225 = 169666^2 + 166235^2 .

It is a cyclic number.

It is not a de Polignac number, because 56420626781 - 2² = 56420626777 is a prime.

It is a super-2 number, since 2×56420626781² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56420626081) 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, 16900856 + ... + 16904193.

It is an arithmetic number, because the mean of its divisors is an integer number (14113608375).

Almost surely, 2^56420626781 is an apocalyptic number.

It is an amenable number.

56420626781 is a deficient number, since it is larger than the sum of its proper divisors (33806719).

56420626781 is a wasteful number, since it uses less digits than its factorization.

56420626781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33806718.

The product of its (nonzero) digits is 967680, while the sum is 47.

The spelling of 56420626781 in words is "fifty-six billion, four hundred twenty million, six hundred twenty-six thousand, seven hundred eighty-one".