115311221 has 16 divisors (see below), whose sum is σ = 128226240. Its totient is φ = 103192320.

The previous prime is 115311211. The next prime is 115311239. The reversal of 115311221 is 122113511.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-115311221 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a self number, because there is not a number n which added to its sum of digits gives 115311221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (115311211) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31286 + ... + 34776.

It is an arithmetic number, because the mean of its divisors is an integer number (8014140).

Almost surely, 2^115311221 is an apocalyptic number.

It is an amenable number.

115311221 is a deficient number, since it is larger than the sum of its proper divisors (12915019).

115311221 is a wasteful number, since it uses less digits than its factorization.

115311221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3604.

The product of its digits is 60, while the sum is 17.

The square root of 115311221 is about 10738.3062444689. The cubic root of 115311221 is about 486.7326992301.

Adding to 115311221 its reverse (122113511), we get a palindrome (237424732).

The spelling of 115311221 in words is "one hundred fifteen million, three hundred eleven thousand, two hundred twenty-one".