129378281 has 4 divisors (see below), whose sum is σ = 130309200. Its totient is φ = 128447364.

The previous prime is 129378269. The next prime is 129378287. The reversal of 129378281 is 182873921.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 129378281 - 2¹⁰ = 129377257 is a prime.

It is a super-2 number, since 2×129378281² = 33477479189029922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129378287) 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, 465251 + ... + 465528.

It is an arithmetic number, because the mean of its divisors is an integer number (32577300).

Almost surely, 2^129378281 is an apocalyptic number.

It is an amenable number.

129378281 is a deficient number, since it is larger than the sum of its proper divisors (930919).

129378281 is an equidigital number, since it uses as much as digits as its factorization.

129378281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 930918.

The product of its digits is 48384, while the sum is 41.

The square root of 129378281 is about 11374.4573936518. The cubic root of 129378281 is about 505.7708464171.

The spelling of 129378281 in words is "one hundred twenty-nine million, three hundred seventy-eight thousand, two hundred eighty-one".