129339421 has 2 divisors, whose sum is σ = 129339422. Its totient is φ = 129339420.

The previous prime is 129339377. The next prime is 129339439. The reversal of 129339421 is 124933921.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 90725625 + 38613796 = 9525^2 + 6214^2 .

It is a cyclic number.

It is not a de Polignac number, because 129339421 - 2¹⁹ = 128815133 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (129339491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64669710 + 64669711.

It is an arithmetic number, because the mean of its divisors is an integer number (64669711).

Almost surely, 2^129339421 is an apocalyptic number.

It is an amenable number.

129339421 is a deficient number, since it is larger than the sum of its proper divisors (1).

129339421 is an equidigital number, since it uses as much as digits as its factorization.

129339421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11664, while the sum is 34.

The square root of 129339421 is about 11372.7490520102. The cubic root of 129339421 is about 505.7202036481.

The spelling of 129339421 in words is "one hundred twenty-nine million, three hundred thirty-nine thousand, four hundred twenty-one".