129851 has 4 divisors (see below), whose sum is σ = 131400. Its totient is φ = 128304.

The previous prime is 129841. The next prime is 129853. The reversal of 129851 is 158921.

It is a happy number.

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 129851 - 2¹⁴ = 113467 is a prime.

It is a super-2 number, since 2×129851² = 33722564402, 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 129851.

It is not an unprimeable number, because it can be changed into a prime (129853) 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 3 ways as a sum of consecutive naturals, for example, 641 + ... + 818.

It is an arithmetic number, because the mean of its divisors is an integer number (32850).

2¹²⁹⁸⁵¹ is an apocalyptic number.

129851 is a deficient number, since it is larger than the sum of its proper divisors (1549).

129851 is an equidigital number, since it uses as much as digits as its factorization.

129851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1548.

The product of its digits is 720, while the sum is 26.

The square root of 129851 is about 360.3484424831. The cubic root of 129851 is about 50.6386088496.

The spelling of 129851 in words is "one hundred twenty-nine thousand, eight hundred fifty-one".