129725285 has 4 divisors (see below), whose sum is σ = 155670348. Its totient is φ = 103780224.

The previous prime is 129725263. The next prime is 129725303. The reversal of 129725285 is 582527921.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 582527921 = 953 ⋅611257.

It can be written as a sum of positive squares in 2 ways, for example, as 87123556 + 42601729 = 9334^2 + 6527^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-129725285 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12972524 + ... + 12972533.

It is an arithmetic number, because the mean of its divisors is an integer number (38917587).

Almost surely, 2^129725285 is an apocalyptic number.

It is an amenable number.

129725285 is a deficient number, since it is larger than the sum of its proper divisors (25945063).

129725285 is an equidigital number, since it uses as much as digits as its factorization.

129725285 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25945062.

The product of its digits is 100800, while the sum is 41.

The square root of 129725285 is about 11389.7008301360. The cubic root of 129725285 is about 506.2226168189. Note that the first 3 decimals are identical.

The spelling of 129725285 in words is "one hundred twenty-nine million, seven hundred twenty-five thousand, two hundred eighty-five".