129381397 has 2 divisors, whose sum is σ = 129381398. Its totient is φ = 129381396.

The previous prime is 129381389. The next prime is 129381401. The reversal of 129381397 is 793183921.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 110796676 + 18584721 = 10526^2 + 4311^2 .

It is an emirp because it is prime and its reverse (793183921) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 129381397 - 2³ = 129381389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (129381997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64690698 + 64690699.

It is an arithmetic number, because the mean of its divisors is an integer number (64690699).

Almost surely, 2^129381397 is an apocalyptic number.

It is an amenable number.

129381397 is a deficient number, since it is larger than the sum of its proper divisors (1).

129381397 is an equidigital number, since it uses as much as digits as its factorization.

129381397 is an evil number, because the sum of its binary digits is even.

The product of its digits is 81648, while the sum is 43.

The square root of 129381397 is about 11374.5943663939. The cubic root of 129381397 is about 505.7749067826.

The spelling of 129381397 in words is "one hundred twenty-nine million, three hundred eighty-one thousand, three hundred ninety-seven".