21138862 has 8 divisors (see below), whose sum is σ = 32481792. Its totient is φ = 10311600.

The previous prime is 21138853. The next prime is 21138881. The reversal of 21138862 is 26883112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 128814 + ... + 128977.

It is an arithmetic number, because the mean of its divisors is an integer number (4060224).

Almost surely, 2^21138862 is an apocalyptic number.

21138862 is a deficient number, since it is larger than the sum of its proper divisors (11342930).

21138862 is a wasteful number, since it uses less digits than its factorization.

21138862 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 257834.

The product of its digits is 4608, while the sum is 31.

The square root of 21138862 is about 4597.7018172126. The cubic root of 21138862 is about 276.4991928490.

The spelling of 21138862 in words is "twenty-one million, one hundred thirty-eight thousand, eight hundred sixty-two".