1215115211 has 4 divisors (see below), whose sum is σ = 1215225792. Its totient is φ = 1215004632.

The previous prime is 1215115183. The next prime is 1215115247. The reversal of 1215115211 is 1125115121.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 1215115211 - 2²⁶ = 1148006347 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1215111211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36731 + ... + 61476.

It is an arithmetic number, because the mean of its divisors is an integer number (303806448).

Almost surely, 2^1215115211 is an apocalyptic number.

1215115211 is a deficient number, since it is larger than the sum of its proper divisors (110581).

1215115211 is an equidigital number, since it uses as much as digits as its factorization.

1215115211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110580.

The product of its digits is 100, while the sum is 20.

The square root of 1215115211 is about 34858.5027073740. The cubic root of 1215115211 is about 1067.1017181192.

The spelling of 1215115211 in words is "one billion, two hundred fifteen million, one hundred fifteen thousand, two hundred eleven".