115664021 has 6 divisors (see below), whose sum is σ = 127134966. Its totient is φ = 105149000.

The previous prime is 115664011. The next prime is 115664027. The reversal of 115664021 is 120466511.

It can be written as a sum of positive squares in only one way, i.e., 114789796 + 874225 = 10714^2 + 935^2 .

It is not a de Polignac number, because 115664021 - 2⁶ = 115663957 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (115664027) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 477830 + ... + 478071.

It is an arithmetic number, because the mean of its divisors is an integer number (21189161).

Almost surely, 2^115664021 is an apocalyptic number.

115664021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

115664021 is a deficient number, since it is larger than the sum of its proper divisors (11470945).

115664021 is an equidigital number, since it uses as much as digits as its factorization.

115664021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 955923 (or 955912 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 115664021 is about 10754.7208703899. The cubic root of 115664021 is about 487.2285875578.

The spelling of 115664021 in words is "one hundred fifteen million, six hundred sixty-four thousand, twenty-one".