115556521 has 2 divisors, whose sum is σ = 115556522. Its totient is φ = 115556520.

The previous prime is 115556489. The next prime is 115556527. The reversal of 115556521 is 125655511.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 115326121 + 230400 = 10739^2 + 480^2 .

It is an emirp because it is prime and its reverse (125655511) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 115556521 - 2⁵ = 115556489 is a prime.

It is not a weakly prime, because it can be changed into another prime (115556527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 57778260 + 57778261.

It is an arithmetic number, because the mean of its divisors is an integer number (57778261).

Almost surely, 2^115556521 is an apocalyptic number.

It is an amenable number.

115556521 is a deficient number, since it is larger than the sum of its proper divisors (1).

115556521 is an equidigital number, since it uses as much as digits as its factorization.

115556521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7500, while the sum is 31.

The square root of 115556521 is about 10749.7219033796. The cubic root of 115556521 is about 487.0775947432.

The spelling of 115556521 in words is "one hundred fifteen million, five hundred fifty-six thousand, five hundred twenty-one".