21879850 has 24 divisors (see below), whose sum is σ = 43092108. Its totient is φ = 8236800.

The previous prime is 21879841. The next prime is 21879881. The reversal of 21879850 is 5897812.

21879850 = T₈₄ + T₈₅ + ... + T₅₀₈.

It can be written as a sum of positive squares in 6 ways, for example, as 13417569 + 8462281 = 3663^2 + 2909^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12021 + ... + 13720.

Almost surely, 2^21879850 is an apocalyptic number.

21879850 is a deficient number, since it is larger than the sum of its proper divisors (21212258).

21879850 is a wasteful number, since it uses less digits than its factorization.

21879850 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25770 (or 25765 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 40.

The square root of 21879850 is about 4677.5901915409. The cubic root of 21879850 is about 279.6929031030.

The spelling of 21879850 in words is "twenty-one million, eight hundred seventy-nine thousand, eight hundred fifty".