66958157 has 6 divisors (see below), whose sum is σ = 77890158. Its totient is φ = 57392664.

The previous prime is 66958141. The next prime is 66958163. The reversal of 66958157 is 75185966.

It can be written as a sum of positive squares in only one way, i.e., 66275881 + 682276 = 8141^2 + 826^2 .

It is not a de Polignac number, because 66958157 - 2⁴ = 66958141 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66958757) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 683198 + ... + 683295.

It is an arithmetic number, because the mean of its divisors is an integer number (12981693).

Almost surely, 2^66958157 is an apocalyptic number.

It is an amenable number.

66958157 is a deficient number, since it is larger than the sum of its proper divisors (10932001).

66958157 is a wasteful number, since it uses less digits than its factorization.

66958157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1366507 (or 1366500 counting only the distinct ones).

The product of its digits is 453600, while the sum is 47.

The square root of 66958157 is about 8182.7964046529. The cubic root of 66958157 is about 406.0702415132.

The spelling of 66958157 in words is "sixty-six million, nine hundred fifty-eight thousand, one hundred fifty-seven".