666752501 has 4 divisors (see below), whose sum is σ = 671227500. Its totient is φ = 662277504.

The previous prime is 666752483. The next prime is 666752521. The reversal of 666752501 is 105257666.

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 96020401 + 570732100 = 9799^2 + 23890^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-666752501 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666752521) 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, 2237276 + ... + 2237573.

It is an arithmetic number, because the mean of its divisors is an integer number (167806875).

Almost surely, 2^666752501 is an apocalyptic number.

It is an amenable number.

666752501 is a deficient number, since it is larger than the sum of its proper divisors (4474999).

666752501 is a wasteful number, since it uses less digits than its factorization.

666752501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4474998.

The product of its (nonzero) digits is 75600, while the sum is 38.

The square root of 666752501 is about 25821.5510959353. The cubic root of 666752501 is about 873.6179547258.

The spelling of 666752501 in words is "six hundred sixty-six million, seven hundred fifty-two thousand, five hundred one".