21073756 has 24 divisors (see below), whose sum is σ = 40360320. Its totient is φ = 9548400.

The previous prime is 21073739. The next prime is 21073799. The reversal of 21073756 is 65737012.

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18771 + ... + 19861.

It is an arithmetic number, because the mean of its divisors is an integer number (1681680).

Almost surely, 2^21073756 is an apocalyptic number.

It is an amenable number.

21073756 is a deficient number, since it is larger than the sum of its proper divisors (19286564).

21073756 is a wasteful number, since it uses less digits than its factorization.

21073756 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1545 (or 1543 counting only the distinct ones).

The product of its (nonzero) digits is 8820, while the sum is 31.

The square root of 21073756 is about 4590.6160806585. The cubic root of 21073756 is about 276.2150358075.

The spelling of 21073756 in words is "twenty-one million, seventy-three thousand, seven hundred fifty-six".