129247 has 4 divisors (see below), whose sum is σ = 129976. Its totient is φ = 128520.

The previous prime is 129229. The next prime is 129263. The reversal of 129247 is 742921.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 742921 = 73 ⋅10177.

It is a cyclic number.

It is not a de Polignac number, because 129247 - 2⁷ = 129119 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129277) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 97 + ... + 517.

It is an arithmetic number, because the mean of its divisors is an integer number (32494).

2¹²⁹²⁴⁷ is an apocalyptic number.

129247 is a deficient number, since it is larger than the sum of its proper divisors (729).

129247 is an equidigital number, since it uses as much as digits as its factorization.

129247 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 728.

The product of its digits is 1008, while the sum is 25.

The square root of 129247 is about 359.5093879164. The cubic root of 129247 is about 50.5599718845.

The spelling of 129247 in words is "one hundred twenty-nine thousand, two hundred forty-seven".