669518729 has 8 divisors (see below), whose sum is σ = 747370272. Its totient is φ = 594498240.

The previous prime is 669518693. The next prime is 669518741. The reversal of 669518729 is 927815966.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 669518729 - 2²⁸ = 401083273 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (669518329) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 707264 + ... + 708209.

It is an arithmetic number, because the mean of its divisors is an integer number (93421284).

Almost surely, 2^669518729 is an apocalyptic number.

It is an amenable number.

669518729 is a deficient number, since it is larger than the sum of its proper divisors (77851543).

669518729 is a wasteful number, since it uses less digits than its factorization.

669518729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1415527.

The product of its digits is 1632960, while the sum is 53.

The square root of 669518729 is about 25875.0599806068. The cubic root of 669518729 is about 874.8244454332.

The spelling of 669518729 in words is "six hundred sixty-nine million, five hundred eighteen thousand, seven hundred twenty-nine".