129149257 has 4 divisors (see below), whose sum is σ = 129256596. Its totient is φ = 129041920.

The previous prime is 129149239. The next prime is 129149263. The reversal of 129149257 is 752941921.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 79995136 + 49154121 = 8944^2 + 7011^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-129149257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129149227) 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, 51844 + ... + 54277.

It is an arithmetic number, because the mean of its divisors is an integer number (32314149).

Almost surely, 2^129149257 is an apocalyptic number.

It is an amenable number.

129149257 is a deficient number, since it is larger than the sum of its proper divisors (107339).

129149257 is a wasteful number, since it uses less digits than its factorization.

129149257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107338.

The product of its digits is 45360, while the sum is 40.

The square root of 129149257 is about 11364.3854651274. The cubic root of 129149257 is about 505.4722334973.

The spelling of 129149257 in words is "one hundred twenty-nine million, one hundred forty-nine thousand, two hundred fifty-seven".