129680869 has 4 divisors (see below), whose sum is σ = 130964940. Its totient is φ = 128396800.

The previous prime is 129680867. The next prime is 129680891. The reversal of 129680869 is 968086921.

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 111302500 + 18378369 = 10550^2 + 4287^2 .

It is a cyclic number.

It is not a de Polignac number, because 129680869 - 2¹ = 129680867 is a prime.

It is a super-2 number, since 2×129680869² = 33634255569190322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129680867) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 641884 + ... + 642085.

It is an arithmetic number, because the mean of its divisors is an integer number (32741235).

Almost surely, 2^129680869 is an apocalyptic number.

It is an amenable number.

129680869 is a deficient number, since it is larger than the sum of its proper divisors (1284071).

129680869 is a wasteful number, since it uses less digits than its factorization.

129680869 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1284070.

The product of its (nonzero) digits is 373248, while the sum is 49.

The square root of 129680869 is about 11387.7508314856. The cubic root of 129680869 is about 506.1648358696.

The spelling of 129680869 in words is "one hundred twenty-nine million, six hundred eighty thousand, eight hundred sixty-nine".