21190668 has 24 divisors (see below), whose sum is σ = 50257200. Its totient is φ = 6947520.

The previous prime is 21190667. The next prime is 21190679. The reversal of 21190668 is 86609112.

It is not an unprimeable number, because it can be changed into a prime (21190661) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13743 + ... + 15206.

It is an arithmetic number, because the mean of its divisors is an integer number (2094050).

Almost surely, 2^21190668 is an apocalyptic number.

It is an amenable number.

21190668 is an abundant number, since it is smaller than the sum of its proper divisors (29066532).

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

21190668 is a wasteful number, since it uses less digits than its factorization.

21190668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29017 (or 29015 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 33.

The square root of 21190668 is about 4603.3322713009. The cubic root of 21190668 is about 276.7248850887.

The spelling of 21190668 in words is "twenty-one million, one hundred ninety thousand, six hundred sixty-eight".