21894628 has 12 divisors (see below), whose sum is σ = 43789312. Its totient is φ = 9383400.

The previous prime is 21894617. The next prime is 21894641. The reversal of 21894628 is 82649812.

21894628 is an admirable number.

It is a hoax number, since the sum of its digits (40) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 390948 + ... + 391003.

Almost surely, 2^21894628 is an apocalyptic number.

21894628 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21894628 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21894628 is a wasteful number, since it uses less digits than its factorization.

21894628 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 781962 (or 781960 counting only the distinct ones).

The product of its digits is 55296, while the sum is 40.

The square root of 21894628 is about 4679.1695844455. The cubic root of 21894628 is about 279.7558586154.

It can be divided in two parts, 21894 and 628, that added together give a palindrome (22522).

The spelling of 21894628 in words is "twenty-one million, eight hundred ninety-four thousand, six hundred twenty-eight".