21392364 has 48 divisors (see below), whose sum is σ = 58596608. Its totient is φ = 5946048.

The previous prime is 21392359. The next prime is 21392381. The reversal of 21392364 is 46329312.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 334 + ... + 6549.

Almost surely, 2^21392364 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21392364, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29298304).

21392364 is an abundant number, since it is smaller than the sum of its proper divisors (37204244).

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

21392364 is a wasteful number, since it uses less digits than its factorization.

21392364 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6934 (or 6932 counting only the distinct ones).

The product of its digits is 7776, while the sum is 30.

The square root of 21392364 is about 4625.1879961792. The cubic root of 21392364 is about 277.6000840192.

The spelling of 21392364 in words is "twenty-one million, three hundred ninety-two thousand, three hundred sixty-four".