129091 has 4 divisors (see below), whose sum is σ = 130032. Its totient is φ = 128152.
The previous prime is 129089. The next prime is 129097. The reversal of 129091 is 190921.
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 is a cyclic number.
It is not a de Polignac number, because 129091 - 21 = 129089 is a prime.
It is a Duffinian number.
It is not an unprimeable number, because it can be changed into a prime (129097) by changing a digit.
It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 220 + ... + 553.
It is an arithmetic number, because the mean of its divisors is an integer number (32508).
2129091 is an apocalyptic number.
129091 is a deficient number, since it is larger than the sum of its proper divisors (941).
129091 is an equidigital number, since it uses as much as digits as its factorization.
129091 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 940.
The product of its (nonzero) digits is 162, while the sum is 22.
The square root of 129091 is about 359.2923600635. The cubic root of 129091 is about 50.5396218801.
It can be divided in two parts, 1 and 29091, that added together give a palindrome (29092).
The spelling of 129091 in words is "one hundred twenty-nine thousand, ninety-one".
• e-mail: info -at- numbersaplenty.com • Privacy notice • done in 0.069 sec. • engine limits •