21103656024 has 128 divisors (see below), whose sum is σ = 58129228800. Its totient is φ = 6331637760.

The previous prime is 21103656019. The next prime is 21103656083. The reversal of 21103656024 is 42065630112.

It is a super-2 number, since 2×21103656024² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21103655982 and 21103656000.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12176662 + ... + 12178394.

It is an arithmetic number, because the mean of its divisors is an integer number (454134600).

Almost surely, 2^21103656024 is an apocalyptic number.

21103656024 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21103656024, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29064614400).

21103656024 is an abundant number, since it is smaller than the sum of its proper divisors (37025572776).

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

21103656024 is a wasteful number, since it uses less digits than its factorization.

21103656024 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2185 (or 2181 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 30.

The spelling of 21103656024 in words is "twenty-one billion, one hundred three million, six hundred fifty-six thousand, twenty-four".