21310440056 has 32 divisors (see below), whose sum is σ = 42107191200. Its totient is φ = 10091030400.

The previous prime is 21310440029. The next prime is 21310440061. The reversal of 21310440056 is 65004401312.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 554771 + ... + 591938.

It is an arithmetic number, because the mean of its divisors is an integer number (1315849725).

Almost surely, 2^21310440056 is an apocalyptic number.

It is an amenable number.

21310440056 is a deficient number, since it is larger than the sum of its proper divisors (20796751144).

21310440056 is a wasteful number, since it uses less digits than its factorization.

21310440056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1146839 (or 1146835 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 26.

Adding to 21310440056 its reverse (65004401312), we get a palindrome (86314841368).

The spelling of 21310440056 in words is "twenty-one billion, three hundred ten million, four hundred forty thousand, fifty-six".