80123581 has 4 divisors (see below), whose sum is σ = 80179164. Its totient is φ = 80068000.

The previous prime is 80123573. The next prime is 80123591. The reversal of 80123581 is 18532108.

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 49420900 + 30702681 = 7030^2 + 5541^2 .

It is a cyclic number.

It is not a de Polignac number, because 80123581 - 2³ = 80123573 is a prime.

It is a super-2 number, since 2×80123581² = 12839576464527122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (80123591) 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, 25570 + ... + 28531.

It is an arithmetic number, because the mean of its divisors is an integer number (20044791).

Almost surely, 2^80123581 is an apocalyptic number.

It is an amenable number.

80123581 is a deficient number, since it is larger than the sum of its proper divisors (55583).

80123581 is a wasteful number, since it uses less digits than its factorization.

80123581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55582.

The product of its (nonzero) digits is 1920, while the sum is 28.

The square root of 80123581 is about 8951.1776320214. The cubic root of 80123581 is about 431.1086965187.

Adding to 80123581 its reverse (18532108), we get a palindrome (98655689).

The spelling of 80123581 in words is "eighty million, one hundred twenty-three thousand, five hundred eighty-one".