129451321 has 2 divisors, whose sum is σ = 129451322. Its totient is φ = 129451320.

The previous prime is 129451213. The next prime is 129451403. The reversal of 129451321 is 123154921.

Together with previous prime (129451213) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 122877225 + 6574096 = 11085^2 + 2564^2 .

It is an emirp because it is prime and its reverse (123154921) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 129451321 - 2¹⁷ = 129320249 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 129451321.

It is not a weakly prime, because it can be changed into another prime (129454321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64725660 + 64725661.

It is an arithmetic number, because the mean of its divisors is an integer number (64725661).

Almost surely, 2^129451321 is an apocalyptic number.

It is an amenable number.

129451321 is a deficient number, since it is larger than the sum of its proper divisors (1).

129451321 is an equidigital number, since it uses as much as digits as its factorization.

129451321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2160, while the sum is 28.

The square root of 129451321 is about 11377.6676432387. The cubic root of 129451321 is about 505.8660054933.

The spelling of 129451321 in words is "one hundred twenty-nine million, four hundred fifty-one thousand, three hundred twenty-one".