21038736 has 40 divisors (see below), whose sum is σ = 54703840. Its totient is φ = 6967296.

The previous prime is 21038729. The next prime is 21038777. The reversal of 21038736 is 63783012.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6480 + ... + 9168.

It is an arithmetic number, because the mean of its divisors is an integer number (1367596).

Almost surely, 2^21038736 is an apocalyptic number.

It is an amenable number.

21038736 is an abundant number, since it is smaller than the sum of its proper divisors (33665104).

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

21038736 is a wasteful number, since it uses less digits than its factorization.

21038736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2863 (or 2857 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 30.

The square root of 21038736 is about 4586.8001918549. The cubic root of 21038736 is about 276.0619478676.

The spelling of 21038736 in words is "twenty-one million, thirty-eight thousand, seven hundred thirty-six".