131023404 has 72 divisors (see below), whose sum is σ = 340773888. Its totient is φ = 42426720.

The previous prime is 131023381. The next prime is 131023423. The reversal of 131023404 is 404320131.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 356829 + ... + 357195.

Almost surely, 2^131023404 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 131023404, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (170386944).

131023404 is an abundant number, since it is smaller than the sum of its proper divisors (209750484).

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

131023404 is a wasteful number, since it uses less digits than its factorization.

131023404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 635 (or 630 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 131023404 is about 11446.5455050858. The cubic root of 131023404 is about 507.9055510853.

Adding to 131023404 its reverse (404320131), we get a palindrome (535343535).

The spelling of 131023404 in words is "one hundred thirty-one million, twenty-three thousand, four hundred four".