21364672 has 56 divisors (see below), whose sum is σ = 49028096. Its totient is φ = 9047808.

The previous prime is 21364669. The next prime is 21364703. The reversal of 21364672 is 27646312.

It is a tau number, because it is divible by the number of its divisors (56).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45913 + ... + 46375.

Almost surely, 2^21364672 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 21364672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24514048).

21364672 is an abundant number, since it is smaller than the sum of its proper divisors (27663424).

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

21364672 is a wasteful number, since it uses less digits than its factorization.

21364672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 585 (or 575 counting only the distinct ones).

The product of its digits is 12096, while the sum is 31.

The square root of 21364672 is about 4622.1934187137. The cubic root of 21364672 is about 277.4802496562.

The spelling of 21364672 in words is "twenty-one million, three hundred sixty-four thousand, six hundred seventy-two".