131861844 has 30 divisors (see below), whose sum is σ = 344713754. Its totient is φ = 43953840.

The previous prime is 131861819. The next prime is 131861857. The reversal of 131861844 is 448168131.

It is a happy number.

131861844 is a `hidden beast` number, since 1 + 31 + 8 + 618 + 4 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 120165444 + 11696400 = 10962^2 + 3420^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 131861799 and 131861808.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 203167 + ... + 203814.

Almost surely, 2^131861844 is an apocalyptic number.

It is an amenable number.

131861844 is an abundant number, since it is smaller than the sum of its proper divisors (212851910).

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

131861844 is a wasteful number, since it uses less digits than its factorization.

131861844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 406997 (or 406986 counting only the distinct ones).

The product of its digits is 18432, while the sum is 36.

The square root of 131861844 is about 11483.1112508762. Note that the first 3 decimals coincide. The cubic root of 131861844 is about 508.9866383195.

The spelling of 131861844 in words is "one hundred thirty-one million, eight hundred sixty-one thousand, eight hundred forty-four".