21331110 has 32 divisors (see below), whose sum is σ = 53890560. Its totient is φ = 5388768.

The previous prime is 21331109. The next prime is 21331127. The reversal of 21331110 is 1113312.

It is a congruent number.

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 15 ways as a sum of consecutive naturals, for example, 18142 + ... + 19281.

It is an arithmetic number, because the mean of its divisors is an integer number (1684080).

Almost surely, 2^21331110 is an apocalyptic number.

21331110 is an abundant number, since it is smaller than the sum of its proper divisors (32559450).

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

21331110 is a wasteful number, since it uses less digits than its factorization.

21331110 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37452.

The product of its (nonzero) digits is 18, while the sum is 12.

The square root of 21331110 is about 4618.5614643523. The cubic root of 21331110 is about 277.3348745728.

Adding to 21331110 its reverse (1113312), we get a palindrome (22444422).

The spelling of 21331110 in words is "twenty-one million, three hundred thirty-one thousand, one hundred ten".