80899999 has 2 divisors, whose sum is σ = 80900000. Its totient is φ = 80899998.

The previous prime is 80899981. The next prime is 80900023. The reversal of 80899999 is 99999808.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 80899999 - 2²¹ = 78802847 is a prime.

80899999 is a modest number, since divided by 9999 gives 8089 as remainder.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (80899919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40449999 + 40450000.

It is an arithmetic number, because the mean of its divisors is an integer number (40450000).

Almost surely, 2^80899999 is an apocalyptic number.

80899999 is a deficient number, since it is larger than the sum of its proper divisors (1).

80899999 is an equidigital number, since it uses as much as digits as its factorization.

80899999 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3779136, while the sum is 61.

The square root of 80899999 is about 8994.4426731177. The cubic root of 80899999 is about 432.4967404835.

The spelling of 80899999 in words is "eighty million, eight hundred ninety-nine thousand, nine hundred ninety-nine".