21938886 has 24 divisors (see below), whose sum is σ = 49068864. Its totient is φ = 7076880.

The previous prime is 21938881. The next prime is 21938899. The reversal of 21938886 is 68883912.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21938881) 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, 19101 + ... + 20216.

It is an arithmetic number, because the mean of its divisors is an integer number (2044536).

Almost surely, 2^21938886 is an apocalyptic number.

21938886 is an abundant number, since it is smaller than the sum of its proper divisors (27129978).

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

21938886 is a wasteful number, since it uses less digits than its factorization.

21938886 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39356 (or 39353 counting only the distinct ones).

The product of its digits is 165888, while the sum is 45.

The square root of 21938886 is about 4683.8964548760. The cubic root of 21938886 is about 279.9442320907.

The spelling of 21938886 in words is "twenty-one million, nine hundred thirty-eight thousand, eight hundred eighty-six".