660071906 has 8 divisors (see below), whose sum is σ = 1066270044. Its totient is φ = 304648560.

The previous prime is 660071879. The next prime is 660071953. The reversal of 660071906 is 609170066.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 644398225 + 15673681 = 25385^2 + 3959^2 .

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, 12693665 + ... + 12693716.

Almost surely, 2^660071906 is an apocalyptic number.

660071906 is a deficient number, since it is larger than the sum of its proper divisors (406198138).

660071906 is a wasteful number, since it uses less digits than its factorization.

660071906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25387396.

The product of its (nonzero) digits is 13608, while the sum is 35.

The square root of 660071906 is about 25691.8645878418. The cubic root of 660071906 is about 870.6903869537.

The spelling of 660071906 in words is "six hundred sixty million, seventy-one thousand, nine hundred six".