21083408 has 10 divisors (see below), whose sum is σ = 40849134. Its totient is φ = 10541696.

The previous prime is 21083399. The next prime is 21083429. The reversal of 21083408 is 80438012.

It can be written as a sum of positive squares in only one way, i.e., 14992384 + 6091024 = 3872^2 + 2468^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 658841 + ... + 658872.

Almost surely, 2^21083408 is an apocalyptic number.

It is an amenable number.

21083408 is a deficient number, since it is larger than the sum of its proper divisors (19765726).

21083408 is a wasteful number, since it uses less digits than its factorization.

21083408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1317721 (or 1317715 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 26.

The square root of 21083408 is about 4591.6672353297. The cubic root of 21083408 is about 276.2571991599.

The spelling of 21083408 in words is "twenty-one million, eighty-three thousand, four hundred eight".