129321229 has 2 divisors, whose sum is σ = 129321230. Its totient is φ = 129321228.

The previous prime is 129321223. The next prime is 129321251. The reversal of 129321229 is 922123921.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 116683204 + 12638025 = 10802^2 + 3555^2 .

It is a cyclic number.

It is not a de Polignac number, because 129321229 - 2¹⁵ = 129288461 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 129321229.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (129321223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64660614 + 64660615.

It is an arithmetic number, because the mean of its divisors is an integer number (64660615).

Almost surely, 2^129321229 is an apocalyptic number.

It is an amenable number.

129321229 is a deficient number, since it is larger than the sum of its proper divisors (1).

129321229 is an equidigital number, since it uses as much as digits as its factorization.

129321229 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3888, while the sum is 31.

The square root of 129321229 is about 11371.9492172626. The cubic root of 129321229 is about 505.6964921526.

It can be divided in two parts, 12932 and 1229, that added together give a square (14161 = 119²).

The spelling of 129321229 in words is "one hundred twenty-nine million, three hundred twenty-one thousand, two hundred twenty-nine".