21083976 has 40 divisors (see below), whose sum is σ = 59056470. Its totient is φ = 7027776.

The previous prime is 21083941. The next prime is 21083989. The reversal of 21083976 is 67938012.

It can be written as a sum of positive squares in only one way, i.e., 21068100 + 15876 = 4590^2 + 126^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 21083976.

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 9 ways as a sum of consecutive naturals, for example, 15621 + ... + 16916.

Almost surely, 2^21083976 is an apocalyptic number.

It is an amenable number.

21083976 is an abundant number, since it is smaller than the sum of its proper divisors (37972494).

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

21083976 is a wasteful number, since it uses less digits than its factorization.

21083976 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32555 (or 32542 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 21083976 is about 4591.7290860851. The cubic root of 21083976 is about 276.2596799840.

It can be divided in two parts, 2108 and 3976, that added together give a square (6084 = 78²).

The spelling of 21083976 in words is "twenty-one million, eighty-three thousand, nine hundred seventy-six".