21731336 has 16 divisors (see below), whose sum is σ = 44450640. Its totient is φ = 9877840.

The previous prime is 21731317. The next prime is 21731363. The reversal of 21731336 is 63313712.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 123386 + ... + 123561.

It is an arithmetic number, because the mean of its divisors is an integer number (2778165).

Almost surely, 2^21731336 is an apocalyptic number.

It is an amenable number.

21731336 is an abundant number, since it is smaller than the sum of its proper divisors (22719304).

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

21731336 is a wasteful number, since it uses less digits than its factorization.

21731336 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 246964 (or 246960 counting only the distinct ones).

The product of its digits is 2268, while the sum is 26.

The square root of 21731336 is about 4661.6881062551. The cubic root of 21731336 is about 279.0586414251.

The spelling of 21731336 in words is "twenty-one million, seven hundred thirty-one thousand, three hundred thirty-six".