66564073257 has 24 divisors (see below), whose sum is σ = 102850825632. Its totient is φ = 37968806400.

The previous prime is 66564073241. The next prime is 66564073271. The reversal of 66564073257 is 75237046566.

It is not a de Polignac number, because 66564073257 - 2⁴ = 66564073241 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is not an unprimeable number, because it can be changed into a prime (66564073207) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3480244 + ... + 3499317.

It is an arithmetic number, because the mean of its divisors is an integer number (4285451068).

Almost surely, 2^66564073257 is an apocalyptic number.

It is an amenable number.

66564073257 is a deficient number, since it is larger than the sum of its proper divisors (36286752375).

66564073257 is a wasteful number, since it uses less digits than its factorization.

66564073257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6979609 (or 6979592 counting only the distinct ones).

The product of its (nonzero) digits is 6350400, while the sum is 51.

The spelling of 66564073257 in words is "sixty-six billion, five hundred sixty-four million, seventy-three thousand, two hundred fifty-seven".