667493947 has 4 divisors (see below), whose sum is σ = 668805840. Its totient is φ = 666182056.

The previous prime is 667493941. The next prime is 667493977. The reversal of 667493947 is 749394766.

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 667493947 - 2²³ = 659105339 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (667493941) 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, 655183 + ... + 656200.

It is an arithmetic number, because the mean of its divisors is an integer number (167201460).

Almost surely, 2^667493947 is an apocalyptic number.

667493947 is a deficient number, since it is larger than the sum of its proper divisors (1311893).

667493947 is a wasteful number, since it uses less digits than its factorization.

667493947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1311892.

The product of its digits is 6858432, while the sum is 55.

The square root of 667493947 is about 25835.9042226124. The cubic root of 667493947 is about 873.9416633403.

The spelling of 667493947 in words is "six hundred sixty-seven million, four hundred ninety-three thousand, nine hundred forty-seven".