21042111312 has 100 divisors (see below), whose sum is σ = 62197941696. Its totient is φ = 6864782400.

The previous prime is 21042111289. The next prime is 21042111323. The reversal of 21042111312 is 21311124012.

21042111312 is a `hidden beast` number, since 210 + 421 + 1 + 1 + 31 + 2 = 666.

It is a super-2 number, since 2×21042111312² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 111814 + ... + 233637.

Almost surely, 2^21042111312 is an apocalyptic number.

It is an amenable number.

21042111312 is an abundant number, since it is smaller than the sum of its proper divisors (41155830384).

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

21042111312 is a wasteful number, since it uses less digits than its factorization.

21042111312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 345518 (or 345503 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

Adding to 21042111312 its reverse (21311124012), we get a palindrome (42353235324).

The spelling of 21042111312 in words is "twenty-one billion, forty-two million, one hundred eleven thousand, three hundred twelve".