21339396 has 48 divisors (see below), whose sum is σ = 59584000. Its totient is φ = 6565536.

The previous prime is 21339391. The next prime is 21339397. The reversal of 21339396 is 69393312.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 21339396.

It is not an unprimeable number, because it can be changed into a prime (21339391) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6196 + ... + 9003.

Almost surely, 2^21339396 is an apocalyptic number.

21339396 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

21339396 is an abundant number, since it is smaller than the sum of its proper divisors (38244604).

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

21339396 is a wasteful number, since it uses less digits than its factorization.

21339396 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15225 (or 15217 counting only the distinct ones).

The product of its digits is 26244, while the sum is 36.

The square root of 21339396 is about 4619.4584098139. The cubic root of 21339396 is about 277.3707798662.

The spelling of 21339396 in words is "twenty-one million, three hundred thirty-nine thousand, three hundred ninety-six".