21803716 has 36 divisors (see below), whose sum is σ = 44166640. Its totient is φ = 9385200.

The previous prime is 21803671. The next prime is 21803729. The reversal of 21803716 is 61730812.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8011 + ... + 10381.

Almost surely, 2^21803716 is an apocalyptic number.

It is an amenable number.

21803716 is an abundant number, since it is smaller than the sum of its proper divisors (22362924).

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

21803716 is a wasteful number, since it uses less digits than its factorization.

21803716 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2416 (or 2403 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 28.

The square root of 21803716 is about 4669.4449348932. Note that the first 3 decimals coincide. The cubic root of 21803716 is about 279.3681158979.

The spelling of 21803716 in words is "twenty-one million, eight hundred three thousand, seven hundred sixteen".