129321251 has 2 divisors, whose sum is σ = 129321252. Its totient is φ = 129321250.

The previous prime is 129321229. The next prime is 129321259. The reversal of 129321251 is 152123921.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (152123921) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 129321251 - 2⁶ = 129321187 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 129321251.

It is not a weakly prime, because it can be changed into another prime (129321259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64660625 + 64660626.

It is an arithmetic number, because the mean of its divisors is an integer number (64660626).

Almost surely, 2^129321251 is an apocalyptic number.

129321251 is a deficient number, since it is larger than the sum of its proper divisors (1).

129321251 is an equidigital number, since it uses as much as digits as its factorization.

129321251 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1080, while the sum is 26.

The square root of 129321251 is about 11371.9501845550. The cubic root of 129321251 is about 505.6965208288.

The spelling of 129321251 in words is "one hundred twenty-nine million, three hundred twenty-one thousand, two hundred fifty-one".