23180971721 has 2 divisors, whose sum is σ = 23180971722. Its totient is φ = 23180971720.

The previous prime is 23180971687. The next prime is 23180971733. The reversal of 23180971721 is 12717908132.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14010036496 + 9170935225 = 118364^2 + 95765^2 .

It is a cyclic number.

It is not a de Polignac number, because 23180971721 - 2¹⁰ = 23180970697 is a prime.

It is not a weakly prime, because it can be changed into another prime (23180971771) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11590485860 + 11590485861.

It is an arithmetic number, because the mean of its divisors is an integer number (11590485861).

Almost surely, 2^23180971721 is an apocalyptic number.

It is an amenable number.

23180971721 is a deficient number, since it is larger than the sum of its proper divisors (1).

23180971721 is an equidigital number, since it uses as much as digits as its factorization.

23180971721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 42336, while the sum is 41.

The spelling of 23180971721 in words is "twenty-three billion, one hundred eighty million, nine hundred seventy-one thousand, seven hundred twenty-one".