21131133111 has 24 divisors (see below), whose sum is σ = 33333225744. Its totient is φ = 12793023360.

The previous prime is 21131133073. The next prime is 21131133173. The reversal of 21131133111 is 11133113112.

21131133111 is a `hidden beast` number, since 2 + 11 + 311 + 331 + 11 = 666.

It is not a de Polignac number, because 21131133111 - 2⁷ = 21131132983 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21131133181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 21136 + ... + 206661.

It is an arithmetic number, because the mean of its divisors is an integer number (1388884406).

Almost surely, 2^21131133111 is an apocalyptic number.

21131133111 is a deficient number, since it is larger than the sum of its proper divisors (12202092633).

21131133111 is a wasteful number, since it uses less digits than its factorization.

21131133111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 228751 (or 228748 counting only the distinct ones).

The product of its digits is 54, while the sum is 18.

Adding to 21131133111 its reverse (11133113112), we get a palindrome (32264246223).

The spelling of 21131133111 in words is "twenty-one billion, one hundred thirty-one million, one hundred thirty-three thousand, one hundred eleven".