66413257 has 4 divisors (see below), whose sum is σ = 67070916. Its totient is φ = 65755600.

The previous prime is 66413159. The next prime is 66413287. The reversal of 66413257 is 75231466.

It is a happy number.

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 63536841 + 2876416 = 7971^2 + 1696^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66413257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66413287) 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, 328678 + ... + 328879.

It is an arithmetic number, because the mean of its divisors is an integer number (16767729).

Almost surely, 2^66413257 is an apocalyptic number.

It is an amenable number.

66413257 is a deficient number, since it is larger than the sum of its proper divisors (657659).

66413257 is a wasteful number, since it uses less digits than its factorization.

66413257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 657658.

The product of its digits is 30240, while the sum is 34.

The square root of 66413257 is about 8149.4329250568. The cubic root of 66413257 is about 404.9657177708.

The spelling of 66413257 in words is "sixty-six million, four hundred thirteen thousand, two hundred fifty-seven".