813810091 has 2 divisors, whose sum is σ = 813810092. Its totient is φ = 813810090.

The previous prime is 813810017. The next prime is 813810097. The reversal of 813810091 is 190018318.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 813810091 - 2⁷ = 813809963 is a prime.

It is not a weakly prime, because it can be changed into another prime (813810097) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 406905045 + 406905046.

It is an arithmetic number, because the mean of its divisors is an integer number (406905046).

Almost surely, 2^813810091 is an apocalyptic number.

813810091 is a deficient number, since it is larger than the sum of its proper divisors (1).

813810091 is an equidigital number, since it uses as much as digits as its factorization.

813810091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728, while the sum is 31.

The square root of 813810091 is about 28527.3568877315. The cubic root of 813810091 is about 933.6290510935.

The spelling of 813810091 in words is "eight hundred thirteen million, eight hundred ten thousand, ninety-one".