66157697 has 2 divisors, whose sum is σ = 66157698. Its totient is φ = 66157696.

The previous prime is 66157687. The next prime is 66157699. The reversal of 66157697 is 79675166.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 50822641 + 15335056 = 7129^2 + 3916^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66157697 is a prime.

Together with 66157699, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (66157699) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33078848 + 33078849.

It is an arithmetic number, because the mean of its divisors is an integer number (33078849).

Almost surely, 2^66157697 is an apocalyptic number.

It is an amenable number.

66157697 is a deficient number, since it is larger than the sum of its proper divisors (1).

66157697 is an equidigital number, since it uses as much as digits as its factorization.

66157697 is an evil number, because the sum of its binary digits is even.

The product of its digits is 476280, while the sum is 47.

The square root of 66157697 is about 8133.7381934754. The cubic root of 66157697 is about 404.4456104106.

The spelling of 66157697 in words is "sixty-six million, one hundred fifty-seven thousand, six hundred ninety-seven".