129249261 has 24 divisors (see below), whose sum is σ = 197433600. Its totient is φ = 81345600.

The previous prime is 129249247. The next prime is 129249269. The reversal of 129249261 is 162942921.

It is not a de Polignac number, because 129249261 - 2¹³ = 129241069 is a prime.

It is a super-2 number, since 2×129249261² = 33410742938092242, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129249269) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5790 + ... + 17088.

It is an arithmetic number, because the mean of its divisors is an integer number (8226400).

Almost surely, 2^129249261 is an apocalyptic number.

It is an amenable number.

129249261 is a deficient number, since it is larger than the sum of its proper divisors (68184339).

129249261 is a wasteful number, since it uses less digits than its factorization.

129249261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11377 (or 11374 counting only the distinct ones).

The product of its digits is 15552, while the sum is 36.

The square root of 129249261 is about 11368.7844996728. The cubic root of 129249261 is about 505.6026670870.

The spelling of 129249261 in words is "one hundred twenty-nine million, two hundred forty-nine thousand, two hundred sixty-one".