21868338 has 16 divisors (see below), whose sum is σ = 44754336. Its totient is φ = 7119840.

The previous prime is 21868337. The next prime is 21868367. The reversal of 21868338 is 83386812.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21868296 and 21868305.

It is not an unprimeable number, because it can be changed into a prime (21868333) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 42123 + ... + 42638.

It is an arithmetic number, because the mean of its divisors is an integer number (2797146).

Almost surely, 2^21868338 is an apocalyptic number.

21868338 is an abundant number, since it is smaller than the sum of its proper divisors (22885998).

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

21868338 is a wasteful number, since it uses less digits than its factorization.

21868338 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84809.

The product of its digits is 55296, while the sum is 39.

The square root of 21868338 is about 4676.3594814770. The cubic root of 21868338 is about 279.6438413778.

The spelling of 21868338 in words is "twenty-one million, eight hundred sixty-eight thousand, three hundred thirty-eight".