21064632 has 48 divisors (see below), whose sum is σ = 55959960. Its totient is φ = 6606336.

The previous prime is 21064627. The next prime is 21064679. The reversal of 21064632 is 23646012.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5418 + ... + 8454.

Almost surely, 2^21064632 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 21064632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27979980).

21064632 is an abundant number, since it is smaller than the sum of its proper divisors (34895328).

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

21064632 is a wasteful number, since it uses less digits than its factorization.

21064632 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3080 (or 3059 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 24.

The square root of 21064632 is about 4589.6222066745. The cubic root of 21064632 is about 276.1751671072.

The spelling of 21064632 in words is "twenty-one million, sixty-four thousand, six hundred thirty-two".