66875257 has 4 divisors (see below), whose sum is σ = 67020160. Its totient is φ = 66730356.

The previous prime is 66875251. The next prime is 66875287. The reversal of 66875257 is 75257866.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 66875257 - 2⁷ = 66875129 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66875251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 71757 + ... + 72682.

It is an arithmetic number, because the mean of its divisors is an integer number (16755040).

Almost surely, 2^66875257 is an apocalyptic number.

It is an amenable number.

66875257 is a deficient number, since it is larger than the sum of its proper divisors (144903).

66875257 is a wasteful number, since it uses less digits than its factorization.

66875257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144902.

The product of its digits is 705600, while the sum is 46.

The square root of 66875257 is about 8177.7293303215. The cubic root of 66875257 is about 405.9025889236.

The spelling of 66875257 in words is "sixty-six million, eight hundred seventy-five thousand, two hundred fifty-seven".