21639050 has 12 divisors (see below), whose sum is σ = 40248726. Its totient is φ = 8655600.

The previous prime is 21639049. The next prime is 21639053. The reversal of 21639050 is 5093612.

It can be written as a sum of positive squares in 3 ways, for example, as 14737921 + 6901129 = 3839^2 + 2627^2 .

It is not an unprimeable number, because it can be changed into a prime (21639053) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 216341 + ... + 216440.

Almost surely, 2^21639050 is an apocalyptic number.

21639050 is a deficient number, since it is larger than the sum of its proper divisors (18609676).

21639050 is a wasteful number, since it uses less digits than its factorization.

21639050 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 432793 (or 432788 counting only the distinct ones).

The product of its (nonzero) digits is 1620, while the sum is 26.

The square root of 21639050 is about 4651.7792294992. The cubic root of 21639050 is about 278.6630567997.

The spelling of 21639050 in words is "twenty-one million, six hundred thirty-nine thousand, fifty".