80841991 has 2 divisors, whose sum is σ = 80841992. Its totient is φ = 80841990.

The previous prime is 80841931. The next prime is 80842049. The reversal of 80841991 is 19914808.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 80841991 - 2⁷ = 80841863 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (80841931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40420995 + 40420996.

It is an arithmetic number, because the mean of its divisors is an integer number (40420996).

Almost surely, 2^80841991 is an apocalyptic number.

80841991 is a deficient number, since it is larger than the sum of its proper divisors (1).

80841991 is an equidigital number, since it uses as much as digits as its factorization.

80841991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20736, while the sum is 40.

The square root of 80841991 is about 8991.2174370327. The cubic root of 80841991 is about 432.3933442330.

The spelling of 80841991 in words is "eighty million, eight hundred forty-one thousand, nine hundred ninety-one".