131121320400 has 480 divisors, whose sum is σ = 534549715200. Its totient is φ = 29904076800.

The previous prime is 131121320387. The next prime is 131121320437. The reversal of 131121320400 is 4023121131.

131121320400 is a `hidden beast` number, since 1 + 31 + 1 + 213 + 20 + 400 = 666.

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

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 95 ways as a sum of consecutive naturals, for example, 39385936 + ... + 39389264.

It is an arithmetic number, because the mean of its divisors is an integer number (1113645240).

Almost surely, 2^131121320400 is an apocalyptic number.

131121320400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 131121320400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (267274857600).

131121320400 is an abundant number, since it is smaller than the sum of its proper divisors (403428394800).

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

131121320400 is a wasteful number, since it uses less digits than its factorization.

131121320400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3884 (or 3867 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 131121320400 its reverse (4023121131), we get a palindrome (135144441531).

The spelling of 131121320400 in words is "one hundred thirty-one billion, one hundred twenty-one million, three hundred twenty thousand, four hundred".