80991889 has 16 divisors (see below), whose sum is σ = 93562560. Its totient is φ = 69336000.

The previous prime is 80991881. The next prime is 80991899. The reversal of 80991889 is 98819908.

It is a cyclic number.

It is not a de Polignac number, because 80991889 - 2³ = 80991881 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (80991881) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 36759 + ... + 38899.

It is an arithmetic number, because the mean of its divisors is an integer number (5847660).

Almost surely, 2^80991889 is an apocalyptic number.

It is an amenable number.

80991889 is a deficient number, since it is larger than the sum of its proper divisors (12570671).

80991889 is a wasteful number, since it uses less digits than its factorization.

80991889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2352.

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

The square root of 80991889 is about 8999.5493776077. The cubic root of 80991889 is about 432.6604285283.

The spelling of 80991889 in words is "eighty million, nine hundred ninety-one thousand, eight hundred eighty-nine".