21676523840 has 28 divisors (see below), whose sum is σ = 51617223156. Its totient is φ = 8670609408.

The previous prime is 21676523809. The next prime is 21676523849. The reversal of 21676523840 is 4832567612.

It can be written as a sum of positive squares in 2 ways, for example, as 14264002624 + 7412521216 = 119432^2 + 86096^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21676523791 and 21676523800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21676523849) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33869249 + ... + 33869888.

Almost surely, 2^21676523840 is an apocalyptic number.

21676523840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21676523840 is an abundant number, since it is smaller than the sum of its proper divisors (29940699316).

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

21676523840 is an equidigital number, since it uses as much as digits as its factorization.

21676523840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67739154 (or 67739144 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 44.

The spelling of 21676523840 in words is "twenty-one billion, six hundred seventy-six million, five hundred twenty-three thousand, eight hundred forty".