115861576981 has 4 divisors (see below), whose sum is σ = 116111818432. Its totient is φ = 115611335532.

The previous prime is 115861576973. The next prime is 115861577009. The reversal of 115861576981 is 189675168511.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 189675168511 = 23 ⋅8246746457.

It is a cyclic number.

It is not a de Polignac number, because 115861576981 - 2³ = 115861576973 is a prime.

It is a super-2 number, since 2×115861576981² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (115861576931) 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, 125120031 + ... + 125120956.

It is an arithmetic number, because the mean of its divisors is an integer number (29027954608).

Almost surely, 2^115861576981 is an apocalyptic number.

It is an amenable number.

115861576981 is a deficient number, since it is larger than the sum of its proper divisors (250241451).

115861576981 is an equidigital number, since it uses as much as digits as its factorization.

115861576981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 250241450.

The product of its digits is 3628800, while the sum is 58.

The spelling of 115861576981 in words is "one hundred fifteen billion, eight hundred sixty-one million, five hundred seventy-six thousand, nine hundred eighty-one".