129905827 has 4 divisors (see below), whose sum is σ = 130278400. Its totient is φ = 129533256.

The previous prime is 129905801. The next prime is 129905843. The reversal of 129905827 is 728509921.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-129905827 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129905327) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 185763 + ... + 186460.

It is an arithmetic number, because the mean of its divisors is an integer number (32569600).

Almost surely, 2^129905827 is an apocalyptic number.

129905827 is a deficient number, since it is larger than the sum of its proper divisors (372573).

129905827 is an equidigital number, since it uses as much as digits as its factorization.

129905827 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 372572.

The product of its (nonzero) digits is 90720, while the sum is 43.

The square root of 129905827 is about 11397.6237435704. The cubic root of 129905827 is about 506.4573489499.

The spelling of 129905827 in words is "one hundred twenty-nine million, nine hundred five thousand, eight hundred twenty-seven".