72021770128 has 40 divisors (see below), whose sum is σ = 173974668480. Its totient is φ = 28060429440.

The previous prime is 72021770111. The next prime is 72021770129. The reversal of 72021770128 is 82107712027.

It is not an unprimeable number, because it can be changed into a prime (72021770129) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29228383 + ... + 29230846.

It is an arithmetic number, because the mean of its divisors is an integer number (4349366712).

Almost surely, 2^72021770128 is an apocalyptic number.

It is an amenable number.

72021770128 is an abundant number, since it is smaller than the sum of its proper divisors (101952898352).

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

72021770128 is a wasteful number, since it uses less digits than its factorization.

72021770128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58459255 (or 58459249 counting only the distinct ones).

The product of its (nonzero) digits is 21952, while the sum is 37.

The spelling of 72021770128 in words is "seventy-two billion, twenty-one million, seven hundred seventy thousand, one hundred twenty-eight".