21678850 has 12 divisors (see below), whose sum is σ = 40322754. Its totient is φ = 8671520.

The previous prime is 21678823. The next prime is 21678907. The reversal of 21678850 is 5887612.

It can be written as a sum of positive squares in 3 ways, for example, as 11812969 + 9865881 = 3437^2 + 3141^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 216739 + ... + 216838.

Almost surely, 2^21678850 is an apocalyptic number.

21678850 is a deficient number, since it is larger than the sum of its proper divisors (18643904).

21678850 is a wasteful number, since it uses less digits than its factorization.

21678850 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 433589 (or 433584 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 37.

The square root of 21678850 is about 4656.0551972673. The cubic root of 21678850 is about 278.8337974585.

The spelling of 21678850 in words is "twenty-one million, six hundred seventy-eight thousand, eight hundred fifty".