131781686400 has 1920 divisors, whose sum is σ = 618774562560. Its totient is φ = 26873856000.

The previous prime is 131781686357. The next prime is 131781686411. The reversal of 131781686400 is 4686187131.

131781686400 is a `hidden beast` number, since 13 + 1 + 78 + 168 + 6 + 400 = 666.

It is a tau number, because it is divible by the number of its divisors (1920).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 872726325 + ... + 872726475.

It is an arithmetic number, because the mean of its divisors is an integer number (322278418).

Almost surely, 2^131781686400 is an apocalyptic number.

131781686400 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 131781686400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (309387281280).

131781686400 is an abundant number, since it is smaller than the sum of its proper divisors (486992876160).

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

131781686400 is a wasteful number, since it uses less digits than its factorization.

131781686400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 244 (or 218 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 45.

The spelling of 131781686400 in words is "one hundred thirty-one billion, seven hundred eighty-one million, six hundred eighty-six thousand, four hundred".