681170018 has 4 divisors (see below), whose sum is σ = 1021755030. Its totient is φ = 340585008.

The previous prime is 681169999. The next prime is 681170029. The reversal of 681170018 is 810071186.

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., 604028929 + 77141089 = 24577^2 + 8783^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 170292503 + ... + 170292506.

Almost surely, 2^681170018 is an apocalyptic number.

681170018 is a deficient number, since it is larger than the sum of its proper divisors (340585012).

681170018 is a wasteful number, since it uses less digits than its factorization.

681170018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 340585011.

The product of its (nonzero) digits is 2688, while the sum is 32.

The square root of 681170018 is about 26099.2340500636. The cubic root of 681170018 is about 879.8699954300.

The spelling of 681170018 in words is "six hundred eighty-one million, one hundred seventy thousand, eighteen".