129666637 has 2 divisors, whose sum is σ = 129666638. Its totient is φ = 129666636.

The previous prime is 129666577. The next prime is 129666643. The reversal of 129666637 is 736666921.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 96707556 + 32959081 = 9834^2 + 5741^2 .

It is a cyclic number.

It is not a de Polignac number, because 129666637 - 2¹⁵ = 129633869 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (129666437) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64833318 + 64833319.

It is an arithmetic number, because the mean of its divisors is an integer number (64833319).

Almost surely, 2^129666637 is an apocalyptic number.

It is an amenable number.

129666637 is a deficient number, since it is larger than the sum of its proper divisors (1).

129666637 is an equidigital number, since it uses as much as digits as its factorization.

129666637 is an evil number, because the sum of its binary digits is even.

The product of its digits is 489888, while the sum is 46.

The square root of 129666637 is about 11387.1259323852. The cubic root of 129666637 is about 506.1463186138.

The spelling of 129666637 in words is "one hundred twenty-nine million, six hundred sixty-six thousand, six hundred thirty-seven".