21329421624 has 96 divisors (see below), whose sum is σ = 66063085920. Its totient is φ = 6090110208.

The previous prime is 21329421599. The next prime is 21329421643. The reversal of 21329421624 is 42612492312.

It is a happy number.

21329421624 is a `hidden beast` number, since 2 + 1 + 3 + 2 + 9 + 4 + 21 + 624 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 799834 + ... + 826070.

It is an arithmetic number, because the mean of its divisors is an integer number (688157145).

Almost surely, 2^21329421624 is an apocalyptic number.

21329421624 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21329421624 is an abundant number, since it is smaller than the sum of its proper divisors (44733664296).

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

21329421624 is a wasteful number, since it uses less digits than its factorization.

21329421624 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27869 (or 27862 counting only the distinct ones).

The product of its digits is 41472, while the sum is 36.

The spelling of 21329421624 in words is "twenty-one billion, three hundred twenty-nine million, four hundred twenty-one thousand, six hundred twenty-four".