815396081 has 2 divisors, whose sum is σ = 815396082. Its totient is φ = 815396080.

The previous prime is 815396063. The next prime is 815396111. The reversal of 815396081 is 180693518.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 449821681 + 365574400 = 21209^2 + 19120^2 .

It is a cyclic number.

It is not a de Polignac number, because 815396081 - 2²⁶ = 748287217 is a prime.

It is a super-2 number, since 2×815396081² = 1329741537820317122, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (815396011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 407698040 + 407698041.

It is an arithmetic number, because the mean of its divisors is an integer number (407698041).

Almost surely, 2^815396081 is an apocalyptic number.

It is an amenable number.

815396081 is a deficient number, since it is larger than the sum of its proper divisors (1).

815396081 is an equidigital number, since it uses as much as digits as its factorization.

815396081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 51840, while the sum is 41.

The square root of 815396081 is about 28555.1410607617. The cubic root of 815396081 is about 934.2351570688.

The spelling of 815396081 in words is "eight hundred fifteen million, three hundred ninety-six thousand, eighty-one".