131286905 has 4 divisors (see below), whose sum is σ = 157544292. Its totient is φ = 105029520.

The previous prime is 131286877. The next prime is 131286949. The reversal of 131286905 is 509682131.

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

It can be written as a sum of positive squares in 2 ways, for example, as 91948921 + 39337984 = 9589^2 + 6272^2 .

It is not a de Polignac number, because 131286905 - 2¹⁴ = 131270521 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

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, 13128686 + ... + 13128695.

It is an arithmetic number, because the mean of its divisors is an integer number (39386073).

Almost surely, 2^131286905 is an apocalyptic number.

It is an amenable number.

131286905 is a deficient number, since it is larger than the sum of its proper divisors (26257387).

131286905 is an equidigital number, since it uses as much as digits as its factorization.

131286905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26257386.

The product of its (nonzero) digits is 12960, while the sum is 35.

The square root of 131286905 is about 11458.0497904312. The cubic root of 131286905 is about 508.2458058263.

The spelling of 131286905 in words is "one hundred thirty-one million, two hundred eighty-six thousand, nine hundred five".