669439726 has 4 divisors (see below), whose sum is σ = 1004159592. Its totient is φ = 334719862.

The previous prime is 669439723. The next prime is 669439739. The reversal of 669439726 is 627934966.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (669439721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 167359930 + ... + 167359933.

It is an arithmetic number, because the mean of its divisors is an integer number (251039898).

Almost surely, 2^669439726 is an apocalyptic number.

669439726 is a deficient number, since it is larger than the sum of its proper divisors (334719866).

669439726 is a wasteful number, since it uses less digits than its factorization.

669439726 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 334719865.

The product of its digits is 2939328, while the sum is 52.

The square root of 669439726 is about 25873.5333110884. The cubic root of 669439726 is about 874.7900344097.

The spelling of 669439726 in words is "six hundred sixty-nine million, four hundred thirty-nine thousand, seven hundred twenty-six".