131665404 has 48 divisors (see below), whose sum is σ = 331914240. Its totient is φ = 40382400.

The previous prime is 131665399. The next prime is 131665433. The reversal of 131665404 is 404566131.

131665404 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×131665404² = 34671557220966432, which contains 22 as substring.

It is a congruent 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 15 ways as a sum of consecutive naturals, for example, 54829 + ... + 57179.

It is an arithmetic number, because the mean of its divisors is an integer number (6914880).

Almost surely, 2^131665404 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 131665404, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (165957120).

131665404 is an abundant number, since it is smaller than the sum of its proper divisors (200248836).

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

131665404 is a wasteful number, since it uses less digits than its factorization.

131665404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2730 (or 2728 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 30.

The square root of 131665404 is about 11474.5546318801. The cubic root of 131665404 is about 508.7337599430.

The spelling of 131665404 in words is "one hundred thirty-one million, six hundred sixty-five thousand, four hundred four".