56821477881 has 64 divisors (see below), whose sum is σ = 92630016000. Its totient is φ = 30262450176.

The previous prime is 56821477879. The next prime is 56821477883. The reversal of 56821477881 is 18877412865.

It is an interprime number because it is at equal distance from previous prime (56821477879) and next prime (56821477883).

It is not a de Polignac number, because 56821477881 - 2¹ = 56821477879 is a prime.

It is a super-2 number, since 2×56821477881² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (57).

It is not an unprimeable number, because it can be changed into a prime (56821477883) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 6172320 + ... + 6181518.

It is an arithmetic number, because the mean of its divisors is an integer number (1447344000).

Almost surely, 2^56821477881 is an apocalyptic number.

It is an amenable number.

56821477881 is a deficient number, since it is larger than the sum of its proper divisors (35808538119).

56821477881 is a wasteful number, since it uses less digits than its factorization.

56821477881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9478.

The product of its digits is 6021120, while the sum is 57.

The spelling of 56821477881 in words is "fifty-six billion, eight hundred twenty-one million, four hundred seventy-seven thousand, eight hundred eighty-one".