131221200 has 120 divisors (see below), whose sum is σ = 458604576. Its totient is φ = 31808000.

The previous prime is 131221193. The next prime is 131221213. The reversal of 131221200 is 2122131.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a nialpdrome in base 8.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8230 + ... + 18170.

Almost surely, 2^131221200 is an apocalyptic number.

131221200 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 131221200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (229302288).

131221200 is an abundant number, since it is smaller than the sum of its proper divisors (327383376).

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

131221200 is a wasteful number, since it uses less digits than its factorization.

131221200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9973 (or 9962 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 131221200 is about 11455.1822333824. The cubic root of 131221200 is about 508.1610046215.

Adding to 131221200 its reverse (2122131), we get a palindrome (133343331).

The spelling of 131221200 in words is "one hundred thirty-one million, two hundred twenty-one thousand, two hundred".