80991718 has 8 divisors (see below), whose sum is σ = 127881720. Its totient is φ = 38364480.

The previous prime is 80991709. The next prime is 80991731. The reversal of 80991718 is 81719908.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1065643 + ... + 1065718.

It is an arithmetic number, because the mean of its divisors is an integer number (15985215).

Almost surely, 2^80991718 is an apocalyptic number.

80991718 is a deficient number, since it is larger than the sum of its proper divisors (46890002).

80991718 is a wasteful number, since it uses less digits than its factorization.

80991718 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2131382.

The product of its (nonzero) digits is 36288, while the sum is 43.

The square root of 80991718 is about 8999.5398771271. The cubic root of 80991718 is about 432.6601240329.

The spelling of 80991718 in words is "eighty million, nine hundred ninety-one thousand, seven hundred eighteen".