129987901 has 2 divisors, whose sum is σ = 129987902. Its totient is φ = 129987900.

The previous prime is 129987887. The next prime is 129987941. The reversal of 129987901 is 109789921.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 128799801 + 1188100 = 11349^2 + 1090^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-129987901 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 (129987941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64993950 + 64993951.

It is an arithmetic number, because the mean of its divisors is an integer number (64993951).

Almost surely, 2^129987901 is an apocalyptic number.

It is an amenable number.

129987901 is a deficient number, since it is larger than the sum of its proper divisors (1).

129987901 is an equidigital number, since it uses as much as digits as its factorization.

129987901 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 81648, while the sum is 46.

The square root of 129987901 is about 11401.2236623969. The cubic root of 129987901 is about 506.5639857615.

The spelling of 129987901 in words is "one hundred twenty-nine million, nine hundred eighty-seven thousand, nine hundred one".