129851819 has 4 divisors (see below), whose sum is σ = 130069200. Its totient is φ = 129634440.

The previous prime is 129851789. The next prime is 129851837. The reversal of 129851819 is 918158921.

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

It is a cyclic number.

It is not a de Polignac number, because 129851819 - 2¹² = 129847723 is a prime.

It is a super-2 number, since 2×129851819² = 33722989795217522, 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 129851819.

It is not an unprimeable number, because it can be changed into a prime (129851849) 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, 107792 + ... + 108989.

It is an arithmetic number, because the mean of its divisors is an integer number (32517300).

Almost surely, 2^129851819 is an apocalyptic number.

129851819 is a deficient number, since it is larger than the sum of its proper divisors (217381).

129851819 is an equidigital number, since it uses as much as digits as its factorization.

129851819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 217380.

The product of its digits is 51840, while the sum is 44.

The square root of 129851819 is about 11395.2542314772. The cubic root of 129851819 is about 506.3871531252.

The spelling of 129851819 in words is "one hundred twenty-nine million, eight hundred fifty-one thousand, eight hundred nineteen".