21302812 has 6 divisors (see below), whose sum is σ = 37279928. Its totient is φ = 10651404.

The previous prime is 21302789. The next prime is 21302833. The reversal of 21302812 is 21820312.

It is a self number, because there is not a number n which added to its sum of digits gives 21302812.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2662848 + ... + 2662855.

Almost surely, 2^21302812 is an apocalyptic number.

It is an amenable number.

21302812 is a deficient number, since it is larger than the sum of its proper divisors (15977116).

21302812 is a wasteful number, since it uses less digits than its factorization.

21302812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5325707 (or 5325705 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 19.

The square root of 21302812 is about 4615.4969396588. The cubic root of 21302812 is about 277.2121821726.

The spelling of 21302812 in words is "twenty-one million, three hundred two thousand, eight hundred twelve".