664067765 has 8 divisors (see below), whose sum is σ = 838822560. Its totient is φ = 503293392.

The previous prime is 664067743. The next prime is 664067779. The reversal of 664067765 is 567760466.

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 664067765 - 2¹² = 664063669 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3494999 + ... + 3495188.

It is an arithmetic number, because the mean of its divisors is an integer number (104852820).

Almost surely, 2^664067765 is an apocalyptic number.

It is an amenable number.

664067765 is a deficient number, since it is larger than the sum of its proper divisors (174754795).

664067765 is a wasteful number, since it uses less digits than its factorization.

664067765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6990211.

The product of its (nonzero) digits is 1270080, while the sum is 47.

The square root of 664067765 is about 25769.5123159132. The cubic root of 664067765 is about 872.4438115665.

The spelling of 664067765 in words is "six hundred sixty-four million, sixty-seven thousand, seven hundred sixty-five".