80691931 has 4 divisors (see below), whose sum is σ = 82872832. Its totient is φ = 78511032.

The previous prime is 80691901. The next prime is 80691953. The reversal of 80691931 is 13919608.

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 80691931 - 2²³ = 72303323 is a prime.

It is a super-2 number, since 2×80691931² = 13022375457017522, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (37), and also a Moran number because the ratio is a prime number: 2180863 = 80691931 / (8 + 0 + 6 + 9 + 1 + 9 + 3 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (80691901) 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, 1090395 + ... + 1090468.

It is an arithmetic number, because the mean of its divisors is an integer number (20718208).

Almost surely, 2^80691931 is an apocalyptic number.

80691931 is a deficient number, since it is larger than the sum of its proper divisors (2180901).

80691931 is a wasteful number, since it uses less digits than its factorization.

80691931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2180900.

The product of its (nonzero) digits is 11664, while the sum is 37.

The square root of 80691931 is about 8982.8687511285. The cubic root of 80691931 is about 432.1256403964.

It can be divided in two parts, 8069 and 1931, that added together give a 4-th power (10000 = 10⁴).

The spelling of 80691931 in words is "eighty million, six hundred ninety-one thousand, nine hundred thirty-one".