20638912 has 56 divisors (see below), whose sum is σ = 48865536. Its totient is φ = 8456448.

The previous prime is 20638861. The next prime is 20638931. The reversal of 20638912 is 21983602.

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

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, 9303 + ... + 11305.

Almost surely, 2^20638912 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 20638912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24432768).

20638912 is an abundant number, since it is smaller than the sum of its proper divisors (28226624).

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

20638912 is a wasteful number, since it uses less digits than its factorization.

20638912 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2045 (or 2035 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 31.

The square root of 20638912 is about 4543.0069337389. The cubic root of 20638912 is about 274.3019740692.

The spelling of 20638912 in words is "twenty million, six hundred thirty-eight thousand, nine hundred twelve".