667279491 has 4 divisors (see below), whose sum is σ = 889705992. Its totient is φ = 444852992.

The previous prime is 667279489. The next prime is 667279507. The reversal of 667279491 is 194972766.

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 667279491 - 2¹ = 667279489 is a prime.

It is not an unprimeable number, because it can be changed into a prime (667279471) 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, 111213246 + ... + 111213251.

It is an arithmetic number, because the mean of its divisors is an integer number (222426498).

Almost surely, 2^667279491 is an apocalyptic number.

667279491 is a deficient number, since it is larger than the sum of its proper divisors (222426501).

667279491 is a wasteful number, since it uses less digits than its factorization.

667279491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 222426500.

The product of its digits is 1143072, while the sum is 51.

The square root of 667279491 is about 25831.7535409426. The cubic root of 667279491 is about 873.8480584420.

The spelling of 667279491 in words is "six hundred sixty-seven million, two hundred seventy-nine thousand, four hundred ninety-one".