21831116 has 12 divisors (see below), whose sum is σ = 38290560. Its totient is φ = 10890960.

The previous prime is 21831101. The next prime is 21831181. The reversal of 21831116 is 61113812.

It is a junction number, because it is equal to n+sod(n) for n = 21831091 and 21831100.

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 3 ways as a sum of consecutive naturals, for example, 4076 + ... + 7763.

It is an arithmetic number, because the mean of its divisors is an integer number (3190880).

Almost surely, 2^21831116 is an apocalyptic number.

It is an amenable number.

21831116 is a deficient number, since it is larger than the sum of its proper divisors (16459444).

21831116 is a wasteful number, since it uses less digits than its factorization.

21831116 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12304 (or 12302 counting only the distinct ones).

The product of its digits is 288, while the sum is 23.

The square root of 21831116 is about 4672.3779812853. The cubic root of 21831116 is about 279.4850910983.

Adding to 21831116 its reverse (61113812), we get a palindrome (82944928).

The spelling of 21831116 in words is "twenty-one million, eight hundred thirty-one thousand, one hundred sixteen".