129800449 has 3 divisors (see below), whose sum is σ = 129811843.
Its totient is φ = 129789056.
The previous prime is 129800443. The next prime is 129800459. The reversal of 129800449 is 944008921.
It is a happy number.
The square root of 129800449 is 11393.
It is a perfect power (a square), and thus also a powerful number.
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.
It can be written as a sum of positive squares in only one way, i.e., 96530625 + 33269824 = 9825^2 + 5768^2
It is a de Polignac number, because none of the positive numbers 2k-129800449 is a prime.
It is a Duffinian number.
It is not an unprimeable number, because it can be changed into a prime (129800443) 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 2 ways as a sum of consecutive naturals, for example, 5697 + ... + 17089.
Almost surely, 2129800449 is an apocalyptic number.
129800449 is the 11393-rd square number.
129800449 is the 5697-th centered octagonal number.
It is an amenable number.
129800449 is a deficient number, since it is larger than the sum of its proper divisors (11394).
129800449 is an frugal number, since it uses more digits than its factorization.
129800449 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 22786 (or 11393 counting only the distinct ones).
The product of its (nonzero) digits is 20736, while the sum is 37.
The cubic root of 129800449 is about 506.3203679252.
Multiplying 129800449 by its product of nonzero digits (20736), we get a square (2691542110464 = 16405922).
The spelling of 129800449 in words is "one hundred twenty-nine million, eight hundred thousand, four hundred forty-nine".