131809545 has 64 divisors (see below), whose sum is σ = 270650880. Its totient is φ = 59616000.

The previous prime is 131809541. The next prime is 131809549. The reversal of 131809545 is 545908131.

131809545 is a `hidden beast` number, since 1 + 31 + 80 + 9 + 545 = 666.

It is an interprime number because it is at equal distance from previous prime (131809541) and next prime (131809549).

It is not a de Polignac number, because 131809545 - 2² = 131809541 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (131809541) 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 63 ways as a sum of consecutive naturals, for example, 94755 + ... + 96135.

It is an arithmetic number, because the mean of its divisors is an integer number (4228920).

Almost surely, 2^131809545 is an apocalyptic number.

131809545 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

131809545 is an abundant number, since it is smaller than the sum of its proper divisors (138841335).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

131809545 is a wasteful number, since it uses less digits than its factorization.

131809545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1503 (or 1497 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 36.

The square root of 131809545 is about 11480.8338111829. The cubic root of 131809545 is about 508.9193380517.

The spelling of 131809545 in words is "one hundred thirty-one million, eight hundred nine thousand, five hundred forty-five".