66157687 has 2 divisors, whose sum is σ = 66157688. Its totient is φ = 66157686.

The previous prime is 66157673. The next prime is 66157697. The reversal of 66157687 is 78675166.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66157687 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66157657) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33078843 + 33078844.

It is an arithmetic number, because the mean of its divisors is an integer number (33078844).

Almost surely, 2^66157687 is an apocalyptic number.

66157687 is a deficient number, since it is larger than the sum of its proper divisors (1).

66157687 is an equidigital number, since it uses as much as digits as its factorization.

66157687 is an evil number, because the sum of its binary digits is even.

The product of its digits is 423360, while the sum is 46.

The square root of 66157687 is about 8133.7375787518. The cubic root of 66157687 is about 404.4455900327.

The spelling of 66157687 in words is "sixty-six million, one hundred fifty-seven thousand, six hundred eighty-seven".