667724089 has 4 divisors (see below), whose sum is σ = 685770724. Its totient is φ = 649677456.

The previous prime is 667724069. The next prime is 667724093. The reversal of 667724089 is 980427766.

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

It can be written as a sum of positive squares in 2 ways, for example, as 635040000 + 32684089 = 25200^2 + 5717^2 .

It is a cyclic number.

It is not a de Polignac number, because 667724089 - 2⁹ = 667723577 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (667724009) 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, 9023262 + ... + 9023335.

It is an arithmetic number, because the mean of its divisors is an integer number (171442681).

Almost surely, 2^667724089 is an apocalyptic number.

It is an amenable number.

667724089 is a deficient number, since it is larger than the sum of its proper divisors (18046635).

667724089 is a wasteful number, since it uses less digits than its factorization.

667724089 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18046634.

The product of its (nonzero) digits is 1016064, while the sum is 49.

The square root of 667724089 is about 25840.3577568113. The cubic root of 667724089 is about 874.0420925012.

The spelling of 667724089 in words is "six hundred sixty-seven million, seven hundred twenty-four thousand, eighty-nine".