21069123712 has 512 divisors, whose sum is σ = 58344652800. Its totient is φ = 7345520640.

The previous prime is 21069123707. The next prime is 21069123727. The reversal of 21069123712 is 21732196012.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 253844823 + ... + 253844905.

It is an arithmetic number, because the mean of its divisors is an integer number (113954400).

Almost surely, 2^21069123712 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 21069123712, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29172326400).

21069123712 is an abundant number, since it is smaller than the sum of its proper divisors (37275529088).

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

21069123712 is a wasteful number, since it uses less digits than its factorization.

21069123712 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 204 (or 192 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 34.

The spelling of 21069123712 in words is "twenty-one billion, sixty-nine million, one hundred twenty-three thousand, seven hundred twelve".