129431377 has 2 divisors, whose sum is σ = 129431378. Its totient is φ = 129431376.

The previous prime is 129431369. The next prime is 129431381. The reversal of 129431377 is 773134921.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 129026881 + 404496 = 11359^2 + 636^2 .

It is a cyclic number.

It is not a de Polignac number, because 129431377 - 2³ = 129431369 is a prime.

It is a super-2 number, since 2×129431377² = 33504962704232258, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (129431317) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64715688 + 64715689.

It is an arithmetic number, because the mean of its divisors is an integer number (64715689).

Almost surely, 2^129431377 is an apocalyptic number.

It is an amenable number.

129431377 is a deficient number, since it is larger than the sum of its proper divisors (1).

129431377 is an equidigital number, since it uses as much as digits as its factorization.

129431377 is an evil number, because the sum of its binary digits is even.

The product of its digits is 31752, while the sum is 37.

The square root of 129431377 is about 11376.7911556818. The cubic root of 129431377 is about 505.8400253032.

The spelling of 129431377 in words is "one hundred twenty-nine million, four hundred thirty-one thousand, three hundred seventy-seven".