667704071 has 4 divisors (see below), whose sum is σ = 689242944. Its totient is φ = 646165200.

The previous prime is 667704049. The next prime is 667704073. The reversal of 667704071 is 170407766.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 667704071 - 2²² = 663509767 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (667704073) 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, 10769390 + ... + 10769451.

It is an arithmetic number, because the mean of its divisors is an integer number (172310736).

Almost surely, 2^667704071 is an apocalyptic number.

667704071 is a deficient number, since it is larger than the sum of its proper divisors (21538873).

667704071 is a wasteful number, since it uses less digits than its factorization.

667704071 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21538872.

The product of its (nonzero) digits is 49392, while the sum is 38.

The square root of 667704071 is about 25839.9704140697. The cubic root of 667704071 is about 874.0333579806.

The spelling of 667704071 in words is "six hundred sixty-seven million, seven hundred four thousand, seventy-one".