129026881 has 9 divisors (see below), whose sum is σ = 133041699. Its totient is φ = 125130744.

The previous prime is 129026879. The next prime is 129026893. The reversal of 129026881 is 188620921.

The square root of 129026881 is 11359.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 115455025 + 13571856 = 10745^2 + 3684^2 .

It is not a de Polignac number, because 129026881 - 2¹ = 129026879 is a prime.

It is a super-2 number, since 2×129026881² = 33295872041176322, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (37).

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 129026881.

It is not an unprimeable number, because it can be changed into a prime (129026861) 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 8 ways as a sum of consecutive naturals, for example, 420130 + ... + 420436.

It is an arithmetic number, because the mean of its divisors is an integer number (14782411).

Almost surely, 2^129026881 is an apocalyptic number.

129026881 is the 11359-th square number.

129026881 is the 5680-th centered octagonal number.

It is an amenable number.

129026881 is a deficient number, since it is larger than the sum of its proper divisors (4014818).

129026881 is an frugal number, since it uses more digits than its factorization.

129026881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 688 (or 344 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 37.

The cubic root of 129026881 is about 505.3125288278.

The spelling of 129026881 in words is "one hundred twenty-nine million, twenty-six thousand, eight hundred eighty-one".