21123732112 has 80 divisors (see below), whose sum is σ = 47937681792. Its totient is φ = 8828467200.

The previous prime is 21123732101. The next prime is 21123732127.

21123732112 is nontrivially palindromic in base 10.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3372888 + ... + 3379144.

Almost surely, 2^21123732112 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21123732112, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23968840896).

21123732112 is an abundant number, since it is smaller than the sum of its proper divisors (26813949680).

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

21123732112 is a wasteful number, since it uses less digits than its factorization.

21123732112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7016 (or 7010 counting only the distinct ones).

The product of its digits is 1008, while the sum is 25.

The spelling of 21123732112 in words is "twenty-one billion, one hundred twenty-three million, seven hundred thirty-two thousand, one hundred twelve".