21873606 has 16 divisors (see below), whose sum is σ = 43867200. Its totient is φ = 7271208.

The previous prime is 21873589. The next prime is 21873613. The reversal of 21873606 is 60637812.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 2536 + ... + 7083.

It is an arithmetic number, because the mean of its divisors is an integer number (2741700).

Almost surely, 2^21873606 is an apocalyptic number.

21873606 is an abundant number, since it is smaller than the sum of its proper divisors (21993594).

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

21873606 is a wasteful number, since it uses less digits than its factorization.

21873606 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10003.

The product of its (nonzero) digits is 12096, while the sum is 33.

The square root of 21873606 is about 4676.9227062247. The cubic root of 21873606 is about 279.6662946232. Note that the first 3 decimals are identical.

The spelling of 21873606 in words is "twenty-one million, eight hundred seventy-three thousand, six hundred six".