131317218 has 54 divisors (see below), whose sum is σ = 296478819. Its totient is φ = 42005952.

The previous prime is 131317217. The next prime is 131317223. The reversal of 131317218 is 812713131.

It is a happy number.

131317218 is a `hidden beast` number, since 131 + 317 + 218 = 666.

It can be written as a sum of positive squares in 5 ways, for example, as 122478489 + 8838729 = 11067^2 + 2973^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=8103.

It is a junction number, because it is equal to n+sod(n) for n = 131317191 and 131317200.

It is not an unprimeable number, because it can be changed into a prime (131317211) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1798830 + ... + 1798902.

Almost surely, 2^131317218 is an apocalyptic number.

131317218 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 131317218

131317218 is an abundant number, since it is smaller than the sum of its proper divisors (165161601).

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

131317218 is an equidigital number, since it uses as much as digits as its factorization.

131317218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 228 (or 115 counting only the distinct ones).

The product of its digits is 1008, while the sum is 27.

The square root of 131317218 is about 11459.3724959092. The cubic root of 131317218 is about 508.2849193224.

The spelling of 131317218 in words is "one hundred thirty-one million, three hundred seventeen thousand, two hundred eighteen".