23173365510721 has 4 divisors (see below), whose sum is σ = 23173387420500. Its totient is φ = 23173343600944.

The previous prime is 23173365510649. The next prime is 23173365510767. The reversal of 23173365510721 is 12701556337132.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8902083780496 + 14271281730225 = 2983636^2 + 3777735^2 .

It is a cyclic number.

It is not a de Polignac number, because 23173365510721 - 2⁹ = 23173365510209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (23173365510791) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9283366 + ... + 11512063.

It is an arithmetic number, because the mean of its divisors is an integer number (5793346855125).

Almost surely, 2^{23173365510721} is an apocalyptic number.

It is an amenable number.

23173365510721 is a deficient number, since it is larger than the sum of its proper divisors (21909779).

23173365510721 is a wasteful number, since it uses less digits than its factorization.

23173365510721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21909778.

The product of its (nonzero) digits is 793800, while the sum is 46.

The spelling of 23173365510721 in words is "twenty-three trillion, one hundred seventy-three billion, three hundred sixty-five million, five hundred ten thousand, seven hundred twenty-one".