115512021 has 8 divisors (see below), whose sum is σ = 171128960. Its totient is φ = 77007996.

The previous prime is 115511971. The next prime is 115512043. The reversal of 115512021 is 120215511.

It is not a de Polignac number, because 115512021 - 2¹⁵ = 115479253 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 115511985 and 115512003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (115512071) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2139085 + ... + 2139138.

It is an arithmetic number, because the mean of its divisors is an integer number (21391120).

Almost surely, 2^115512021 is an apocalyptic number.

It is an amenable number.

115512021 is a deficient number, since it is larger than the sum of its proper divisors (55616939).

115512021 is an equidigital number, since it uses as much as digits as its factorization.

115512021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4278232 (or 4278226 counting only the distinct ones).

The product of its (nonzero) digits is 100, while the sum is 18.

The square root of 115512021 is about 10747.6518830859. The cubic root of 115512021 is about 487.0150633353.

Adding to 115512021 its reverse (120215511), we get a palindrome (235727532).

The spelling of 115512021 in words is "one hundred fifteen million, five hundred twelve thousand, twenty-one".