23115087981 has 12 divisors (see below), whose sum is σ = 33442935708. Its totient is φ = 15384916224.

The previous prime is 23115087977. The next prime is 23115088043. The reversal of 23115087981 is 18978051132.

It can be written as a sum of positive squares in 2 ways, for example, as 2742093225 + 20372994756 = 52365^2 + 142734^2 .

It is not a de Polignac number, because 23115087981 - 2² = 23115087977 is a prime.

It is a super-2 number, since 2×23115087981² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23115087481) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2089380 + ... + 2100413.

It is an arithmetic number, because the mean of its divisors is an integer number (2786911309).

Almost surely, 2^23115087981 is an apocalyptic number.

It is an amenable number.

23115087981 is a deficient number, since it is larger than the sum of its proper divisors (10327847727).

23115087981 is a wasteful number, since it uses less digits than its factorization.

23115087981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4190412 (or 4190409 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 45.

The spelling of 23115087981 in words is "twenty-three billion, one hundred fifteen million, eighty-seven thousand, nine hundred eighty-one".