129275819 has 4 divisors (see below), whose sum is σ = 129845544. Its totient is φ = 128706096.

The previous prime is 129275777. The next prime is 129275831. The reversal of 129275819 is 918572921.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-129275819 is a prime.

It is a super-2 number, since 2×129275819² = 33424474756241522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 129275819.

It is not an unprimeable number, because it can be changed into a prime (129275849) 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, 284522 + ... + 284975.

It is an arithmetic number, because the mean of its divisors is an integer number (32461386).

Almost surely, 2^129275819 is an apocalyptic number.

129275819 is a deficient number, since it is larger than the sum of its proper divisors (569725).

129275819 is an equidigital number, since it uses as much as digits as its factorization.

129275819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 569724.

The product of its digits is 90720, while the sum is 44.

The square root of 129275819 is about 11369.9524625216. The cubic root of 129275819 is about 505.6372949472.

The spelling of 129275819 in words is "one hundred twenty-nine million, two hundred seventy-five thousand, eight hundred nineteen".