21083490 has 40 divisors (see below), whose sum is σ = 56693340. Its totient is φ = 5622048.

The previous prime is 21083449. The next prime is 21083537. The reversal of 21083490 is 9438012.

It can be written as a sum of positive squares in 2 ways, for example, as 18429849 + 2653641 = 4293^2 + 1629^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

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 19 ways as a sum of consecutive naturals, for example, 12205 + ... + 13824.

Almost surely, 2^21083490 is an apocalyptic number.

21083490 is an abundant number, since it is smaller than the sum of its proper divisors (35609850).

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

21083490 is a wasteful number, since it uses less digits than its factorization.

21083490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26048 (or 26039 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 21083490 is about 4591.6761645395. The cubic root of 21083490 is about 276.2575573098.

The spelling of 21083490 in words is "twenty-one million, eighty-three thousand, four hundred ninety".