809749018 has 8 divisors (see below), whose sum is σ = 1308056148. Its totient is φ = 373730304.

The previous prime is 809749007. The next prime is 809749037. The reversal of 809749018 is 810947908.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 809004249 + 744769 = 28443^2 + 863^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15572071 + ... + 15572122.

Almost surely, 2^809749018 is an apocalyptic number.

809749018 is a deficient number, since it is larger than the sum of its proper divisors (498307130).

809749018 is a wasteful number, since it uses less digits than its factorization.

809749018 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31144208.

The product of its (nonzero) digits is 145152, while the sum is 46.

The square root of 809749018 is about 28456.0892956147. The cubic root of 809749018 is about 932.0734628985.

The spelling of 809749018 in words is "eight hundred nine million, seven hundred forty-nine thousand, eighteen".