21405633632 has 36 divisors (see below), whose sum is σ = 42233760828. Its totient is φ = 10679644800.

The previous prime is 21405633617. The next prime is 21405633653. The reversal of 21405633632 is 23633650412.

It is a super-2 number, since 2×21405633632² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21405633592 and 21405633601.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 13980707 + ... + 13982237.

It is an arithmetic number, because the mean of its divisors is an integer number (1173160023).

Almost surely, 2^21405633632 is an apocalyptic number.

It is an amenable number.

21405633632 is a deficient number, since it is larger than the sum of its proper divisors (20828127196).

21405633632 is an frugal number, since it uses more digits than its factorization.

21405633632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2863 (or 2194 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 35.

The spelling of 21405633632 in words is "twenty-one billion, four hundred five million, six hundred thirty-three thousand, six hundred thirty-two".