80517818 has 4 divisors (see below), whose sum is σ = 120776730. Its totient is φ = 40258908.

The previous prime is 80517817. The next prime is 80517841. The reversal of 80517818 is 81871508.

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

It can be written as a sum of positive squares in only one way, i.e., 54272689 + 26245129 = 7367^2 + 5123^2 .

It is a super-2 number, since 2×80517818² = 12966238030962248, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (80517817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20129453 + ... + 20129456.

Almost surely, 2^80517818 is an apocalyptic number.

80517818 is a deficient number, since it is larger than the sum of its proper divisors (40258912).

80517818 is a wasteful number, since it uses less digits than its factorization.

80517818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40258911.

The product of its (nonzero) digits is 17920, while the sum is 38.

The square root of 80517818 is about 8973.1721258427. The cubic root of 80517818 is about 431.8146102389.

The spelling of 80517818 in words is "eighty million, five hundred seventeen thousand, eight hundred eighteen".