131905205 has 4 divisors (see below), whose sum is σ = 158286252. Its totient is φ = 105524160.

The previous prime is 131905183. The next prime is 131905229. The reversal of 131905205 is 502509131.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 502509131 = 19 ⋅26447849.

It can be written as a sum of positive squares in 2 ways, for example, as 21613201 + 110292004 = 4649^2 + 10502^2 .

It is not a de Polignac number, because 131905205 - 2¹⁴ = 131888821 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13190516 + ... + 13190525.

It is an arithmetic number, because the mean of its divisors is an integer number (39571563).

Almost surely, 2^131905205 is an apocalyptic number.

It is an amenable number.

131905205 is a deficient number, since it is larger than the sum of its proper divisors (26381047).

131905205 is an equidigital number, since it uses as much as digits as its factorization.

131905205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26381046.

The product of its (nonzero) digits is 1350, while the sum is 26.

The square root of 131905205 is about 11484.9991292991. Note that the first 3 decimals coincide. The cubic root of 131905205 is about 509.0424233499.

The spelling of 131905205 in words is "one hundred thirty-one million, nine hundred five thousand, two hundred five".