129520347 has 16 divisors (see below), whose sum is σ = 189388800. Its totient is φ = 78082400.

The previous prime is 129520333. The next prime is 129520361. The reversal of 129520347 is 743025921.

It is an interprime number because it is at equal distance from previous prime (129520333) and next prime (129520361).

It is not a de Polignac number, because 129520347 - 2⁷ = 129520219 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (129520747) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3972 + ... + 16577.

It is an arithmetic number, because the mean of its divisors is an integer number (11836800).

Almost surely, 2^129520347 is an apocalyptic number.

129520347 is a deficient number, since it is larger than the sum of its proper divisors (59868453).

129520347 is a wasteful number, since it uses less digits than its factorization.

129520347 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20754.

The product of its (nonzero) digits is 15120, while the sum is 33.

The square root of 129520347 is about 11380.7006374827. The cubic root of 129520347 is about 505.9559020973.

The spelling of 129520347 in words is "one hundred twenty-nine million, five hundred twenty thousand, three hundred forty-seven".