129681947 has 2 divisors, whose sum is σ = 129681948. Its totient is φ = 129681946.

The previous prime is 129681907. The next prime is 129681991. The reversal of 129681947 is 749186921.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 129681947 - 2¹² = 129677851 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (129681907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64840973 + 64840974.

It is an arithmetic number, because the mean of its divisors is an integer number (64840974).

Almost surely, 2^129681947 is an apocalyptic number.

129681947 is a deficient number, since it is larger than the sum of its proper divisors (1).

129681947 is an equidigital number, since it uses as much as digits as its factorization.

129681947 is an evil number, because the sum of its binary digits is even.

The product of its digits is 217728, while the sum is 47.

The square root of 129681947 is about 11387.7981629462. The cubic root of 129681947 is about 506.1662384003.

The spelling of 129681947 in words is "one hundred twenty-nine million, six hundred eighty-one thousand, nine hundred forty-seven".