23009552721 has 27 divisors (see below), whose sum is σ = 33848387131. Its totient is φ = 15062110944.

The previous prime is 23009552689. The next prime is 23009552807. The reversal of 23009552721 is 12725590032.

The square root of 23009552721 is 151689.

It is a perfect power (a square), and thus also a powerful number.

23009552721 is a `hidden beast` number, since 2 + 30 + 0 + 9 + 552 + 72 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 21323300625 + 1686252096 = 146025^2 + 41064^2 .

It is not a de Polignac number, because 23009552721 - 2⁵ = 23009552689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (23009552021) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 26848525 + ... + 26849381.

Almost surely, 2^23009552721 is an apocalyptic number.

23009552721 is the 151689-th square number.

23009552721 is the 75845-th centered octagonal number.

It is an amenable number.

23009552721 is a deficient number, since it is larger than the sum of its proper divisors (10838834410).

23009552721 is an frugal number, since it uses more digits than its factorization.

23009552721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1838 (or 919 counting only the distinct ones).

The product of its (nonzero) digits is 37800, while the sum is 36.

Multiplying 23009552721 by its sum of digits (36), we get a square (828343897956 = 910134²).

The spelling of 23009552721 in words is "twenty-three billion, nine million, five hundred fifty-two thousand, seven hundred twenty-one".