56861288781 has 32 divisors (see below), whose sum is σ = 91379985408. Its totient is φ = 31024055040.

The previous prime is 56861288777. The next prime is 56861288789. The reversal of 56861288781 is 18788216865.

It is not a de Polignac number, because 56861288781 - 2² = 56861288777 is a prime.

It is a super-2 number, since 2×56861288781² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56861288789) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2190511 + ... + 2216316.

It is an arithmetic number, because the mean of its divisors is an integer number (2855624544).

Almost surely, 2^56861288781 is an apocalyptic number.

56861288781 is a gapful number since it is divisible by the number (51) formed by its first and last digit.

It is an amenable number.

56861288781 is a deficient number, since it is larger than the sum of its proper divisors (34518696627).

56861288781 is a wasteful number, since it uses less digits than its factorization.

56861288781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4406881.

The product of its digits is 10321920, while the sum is 60.

The spelling of 56861288781 in words is "fifty-six billion, eight hundred sixty-one million, two hundred eighty-eight thousand, seven hundred eighty-one".