21132111 has 64 divisors (see below), whose sum is σ = 39223296. Its totient is φ = 9763200.

The previous prime is 21132103. The next prime is 21132119. The reversal of 21132111 is 11123112.

It is an interprime number because it is at equal distance from previous prime (21132103) and next prime (21132119).

It is not a de Polignac number, because 21132111 - 2³ = 21132103 is a prime.

It is a super-2 number, since 2×21132111² = 893132230632642, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21132119) 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 63 ways as a sum of consecutive naturals, for example, 92980 + ... + 93206.

It is an arithmetic number, because the mean of its divisors is an integer number (612864).

Almost surely, 2^21132111 is an apocalyptic number.

21132111 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21132111 is a deficient number, since it is larger than the sum of its proper divisors (18091185).

21132111 is a wasteful number, since it uses less digits than its factorization.

21132111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 292.

The product of its digits is 12, while the sum is 12.

The square root of 21132111 is about 4596.9675874428. The cubic root of 21132111 is about 276.4697550486.

Adding to 21132111 its reverse (11123112), we get a palindrome (32255223).

It can be divided in two parts, 2113 and 2111, that added together give a palindrome (4224).

The spelling of 21132111 in words is "twenty-one million, one hundred thirty-two thousand, one hundred eleven".