80999881 has 2 divisors, whose sum is σ = 80999882. Its totient is φ = 80999880.

The previous prime is 80999857. The next prime is 80999903. The reversal of 80999881 is 18899908.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 62647225 + 18352656 = 7915^2 + 4284^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-80999881 is a prime.

It is a super-2 number, since 2×80999881² = 13121961444028322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (80999081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40499940 + 40499941.

It is an arithmetic number, because the mean of its divisors is an integer number (40499941).

Almost surely, 2^80999881 is an apocalyptic number.

It is an amenable number.

80999881 is a deficient number, since it is larger than the sum of its proper divisors (1).

80999881 is an equidigital number, since it uses as much as digits as its factorization.

80999881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 373248, while the sum is 52.

The square root of 80999881 is about 8999.9933888865. The cubic root of 80999881 is about 432.6746592061.

The spelling of 80999881 in words is "eighty million, nine hundred ninety-nine thousand, eight hundred eighty-one".