21631654 has 12 divisors (see below), whose sum is σ = 35665812. Its totient is φ = 9832460.

The previous prime is 21631639. The next prime is 21631663. The reversal of 21631654 is 45613612.

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, 44452 + ... + 44935.

It is an arithmetic number, because the mean of its divisors is an integer number (2972151).

Almost surely, 2^21631654 is an apocalyptic number.

21631654 is a deficient number, since it is larger than the sum of its proper divisors (14034158).

21631654 is a wasteful number, since it uses less digits than its factorization.

21631654 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89411 (or 89400 counting only the distinct ones).

The product of its digits is 4320, while the sum is 28.

The square root of 21631654 is about 4650.9841969200. The cubic root of 21631654 is about 278.6313051467.

The spelling of 21631654 in words is "twenty-one million, six hundred thirty-one thousand, six hundred fifty-four".