21613984440 has 64 divisors (see below), whose sum is σ = 64898703360. Its totient is φ = 5758684800.

The previous prime is 21613984439. The next prime is 21613984453. The reversal of 21613984440 is 4448931612.

It is a super-2 number, since 2×21613984440² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21613984392 and 21613984401.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 59877 + ... + 216363.

It is an arithmetic number, because the mean of its divisors is an integer number (1014042240).

Almost surely, 2^21613984440 is an apocalyptic number.

21613984440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21613984440 is an abundant number, since it is smaller than the sum of its proper divisors (43284718920).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21613984440 is a wasteful number, since it uses less digits than its factorization.

21613984440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157652 (or 157648 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 42.

The spelling of 21613984440 in words is "twenty-one billion, six hundred thirteen million, nine hundred eighty-four thousand, four hundred forty".