815225911 has 2 divisors, whose sum is σ = 815225912. Its totient is φ = 815225910.

The previous prime is 815225909. The next prime is 815225953. The reversal of 815225911 is 119522518.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 815225911 - 2¹ = 815225909 is a prime.

Together with 815225909, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (815225111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 407612955 + 407612956.

It is an arithmetic number, because the mean of its divisors is an integer number (407612956).

Almost surely, 2^815225911 is an apocalyptic number.

815225911 is a deficient number, since it is larger than the sum of its proper divisors (1).

815225911 is an equidigital number, since it uses as much as digits as its factorization.

815225911 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7200, while the sum is 34.

The square root of 815225911 is about 28552.1612316826. The cubic root of 815225911 is about 934.1701621290.

The spelling of 815225911 in words is "eight hundred fifteen million, two hundred twenty-five thousand, nine hundred eleven".