115021221 has 16 divisors (see below), whose sum is σ = 181315200. Its totient is φ = 63459648.

The previous prime is 115021219. The next prime is 115021223. The reversal of 115021221 is 122120511.

It is an interprime number because it is at equal distance from previous prime (115021219) and next prime (115021223).

It is not a de Polignac number, because 115021221 - 2¹ = 115021219 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 115021221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (115021223) 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, 93826 + ... + 95043.

It is an arithmetic number, because the mean of its divisors is an integer number (11332200).

Almost surely, 2^115021221 is an apocalyptic number.

It is an amenable number.

115021221 is a deficient number, since it is larger than the sum of its proper divisors (66293979).

115021221 is a wasteful number, since it uses less digits than its factorization.

115021221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 188908.

The product of its (nonzero) digits is 40, while the sum is 15.

The square root of 115021221 is about 10724.7946833494. The cubic root of 115021221 is about 486.3243233096.

Adding to 115021221 its reverse (122120511), we get a palindrome (237141732).

The spelling of 115021221 in words is "one hundred fifteen million, twenty-one thousand, two hundred twenty-one".