80081999 has 4 divisors (see below), whose sum is σ = 80155320. Its totient is φ = 80008680.

The previous prime is 80081983. The next prime is 80082001. The reversal of 80081999 is 99918008.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 80081999 - 2⁴ = 80081983 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (80081899) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34997 + ... + 37214.

It is an arithmetic number, because the mean of its divisors is an integer number (20038830).

Almost surely, 2^80081999 is an apocalyptic number.

80081999 is a deficient number, since it is larger than the sum of its proper divisors (73321).

80081999 is a wasteful number, since it uses less digits than its factorization.

80081999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73320.

The product of its (nonzero) digits is 46656, while the sum is 44.

The square root of 80081999 is about 8948.8546194471. The cubic root of 80081999 is about 431.0341056446.

The spelling of 80081999 in words is "eighty million, eighty-one thousand, nine hundred ninety-nine".