80991473 has 4 divisors (see below), whose sum is σ = 82519668. Its totient is φ = 79463280.

The previous prime is 80991439. The next prime is 80991503. The reversal of 80991473 is 37419908.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 72880369 + 8111104 = 8537^2 + 2848^2 .

It is a cyclic number.

It is not a de Polignac number, because 80991473 - 2¹⁰ = 80990449 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 80991473.

It is not an unprimeable number, because it can be changed into a prime (80991413) 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, 764018 + ... + 764123.

It is an arithmetic number, because the mean of its divisors is an integer number (20629917).

Almost surely, 2^80991473 is an apocalyptic number.

It is an amenable number.

80991473 is a deficient number, since it is larger than the sum of its proper divisors (1528195).

80991473 is a wasteful number, since it uses less digits than its factorization.

80991473 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1528194.

The product of its (nonzero) digits is 54432, while the sum is 41.

The square root of 80991473 is about 8999.5262653097. The cubic root of 80991473 is about 432.6596877667.

The spelling of 80991473 in words is "eighty million, nine hundred ninety-one thousand, four hundred seventy-three".