21876231 has 8 divisors (see below), whose sum is σ = 31412080. Its totient is φ = 13462272.

The previous prime is 21876221. The next prime is 21876233. The reversal of 21876231 is 13267812.

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

It is not a de Polignac number, because 21876231 - 2⁵ = 21876199 is a prime.

It is a super-2 number, since 2×21876231² = 957138965530722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21876233) by changing a digit.

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, 280426 + ... + 280503.

It is an arithmetic number, because the mean of its divisors is an integer number (3926510).

Almost surely, 2^21876231 is an apocalyptic number.

21876231 is a deficient number, since it is larger than the sum of its proper divisors (9535849).

21876231 is a wasteful number, since it uses less digits than its factorization.

21876231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 560945.

The product of its digits is 4032, while the sum is 30.

The square root of 21876231 is about 4677.2033310516. The cubic root of 21876231 is about 279.6774815404.

The spelling of 21876231 in words is "twenty-one million, eight hundred seventy-six thousand, two hundred thirty-one".