21490588 has 12 divisors (see below), whose sum is σ = 42981232. Its totient is φ = 9210240.

The previous prime is 21490541. The next prime is 21490589. The reversal of 21490588 is 88509412.

21490588 is an admirable number.

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21490589) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 383733 + ... + 383788.

Almost surely, 2^21490588 is an apocalyptic number.

21490588 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21490588 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.

21490588 is a wasteful number, since it uses less digits than its factorization.

21490588 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 767532 (or 767530 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 37.

The square root of 21490588 is about 4635.7942145872. The cubic root of 21490588 is about 278.0243064854.

The spelling of 21490588 in words is "twenty-one million, four hundred ninety thousand, five hundred eighty-eight".