21338188 has 12 divisors (see below), whose sum is σ = 38136672. Its totient is φ = 10442000.

The previous prime is 21338183. The next prime is 21338189. The reversal of 21338188 is 88183312.

It is not an unprimeable number, because it can be changed into a prime (21338183) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 56563 + ... + 56938.

It is an arithmetic number, because the mean of its divisors is an integer number (3178056).

Almost surely, 2^21338188 is an apocalyptic number.

It is an amenable number.

21338188 is a deficient number, since it is larger than the sum of its proper divisors (16798484).

21338188 is a wasteful number, since it uses less digits than its factorization.

21338188 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113552 (or 113550 counting only the distinct ones).

The product of its digits is 9216, while the sum is 34.

The square root of 21338188 is about 4619.3276567050. The cubic root of 21338188 is about 277.3655458813.

The spelling of 21338188 in words is "twenty-one million, three hundred thirty-eight thousand, one hundred eighty-eight".