11215815 has 32 divisors (see below), whose sum is σ = 19535040. Its totient is φ = 5462016.

The previous prime is 11215811. The next prime is 11215823. The reversal of 11215815 is 51851211.

11215815 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 11215815 - 2² = 11215811 is a prime.

It is a super-2 number, since 2×11215815² = 251589012228450, which contains 22 as substring.

It is a nialpdrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11215811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 21781 + ... + 22289.

It is an arithmetic number, because the mean of its divisors is an integer number (610470).

Almost surely, 2^11215815 is an apocalyptic number.

11215815 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

11215815 is a deficient number, since it is larger than the sum of its proper divisors (8319225).

11215815 is a wasteful number, since it uses less digits than its factorization.

11215815 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 643.

The product of its digits is 400, while the sum is 24.

The square root of 11215815 is about 3349.0020901755. The cubic root of 11215815 is about 223.8430488018.

The spelling of 11215815 in words is "eleven million, two hundred fifteen thousand, eight hundred fifteen".