129378647 has 2 divisors, whose sum is σ = 129378648. Its totient is φ = 129378646.

The previous prime is 129378643. The next prime is 129378661. The reversal of 129378647 is 746873921.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 129378647 - 2² = 129378643 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (129378643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64689323 + 64689324.

It is an arithmetic number, because the mean of its divisors is an integer number (64689324).

Almost surely, 2^129378647 is an apocalyptic number.

129378647 is a deficient number, since it is larger than the sum of its proper divisors (1).

129378647 is an equidigital number, since it uses as much as digits as its factorization.

129378647 is an evil number, because the sum of its binary digits is even.

The product of its digits is 508032, while the sum is 47.

The square root of 129378647 is about 11374.4734823200. The cubic root of 129378647 is about 505.7713233441.

The spelling of 129378647 in words is "one hundred twenty-nine million, three hundred seventy-eight thousand, six hundred forty-seven".