21239950 has 24 divisors (see below), whose sum is σ = 39785400. Its totient is φ = 8436000.

The previous prime is 21239923. The next prime is 21239957. The reversal of 21239950 is 5993212.

It is a super-2 number, since 2×21239950² = 902270952005000, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21239957) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6025 + ... + 8875.

It is an arithmetic number, because the mean of its divisors is an integer number (1657725).

Almost surely, 2^21239950 is an apocalyptic number.

21239950 is a deficient number, since it is larger than the sum of its proper divisors (18545450).

21239950 is a wasteful number, since it uses less digits than its factorization.

21239950 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3012 (or 3007 counting only the distinct ones).

The product of its (nonzero) digits is 4860, while the sum is 31.

The square root of 21239950 is about 4608.6820241800. The cubic root of 21239950 is about 276.9392404106.

The spelling of 21239950 in words is "twenty-one million, two hundred thirty-nine thousand, nine hundred fifty".