21338694 has 64 divisors (see below), whose sum is σ = 51710400. Its totient is φ = 6483456.

The previous prime is 21338683. The next prime is 21338717. The reversal of 21338694 is 49683312.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 79192 + ... + 79460.

It is an arithmetic number, because the mean of its divisors is an integer number (807975).

Almost surely, 2^21338694 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21338694, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25855200).

21338694 is an abundant number, since it is smaller than the sum of its proper divisors (30371706).

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

21338694 is a wasteful number, since it uses less digits than its factorization.

21338694 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 406 (or 400 counting only the distinct ones).

The product of its digits is 31104, while the sum is 36.

The square root of 21338694 is about 4619.3824262557. The cubic root of 21338694 is about 277.3677382864.

The spelling of 21338694 in words is "twenty-one million, three hundred thirty-eight thousand, six hundred ninety-four".