131721201 has 32 divisors (see below), whose sum is σ = 202583040. Its totient is φ = 84499200.

The previous prime is 131721199. The next prime is 131721209. The reversal of 131721201 is 102127131.

It is a happy number.

It is not a de Polignac number, because 131721201 - 2¹ = 131721199 is a prime.

It is not an unprimeable number, because it can be changed into a prime (131721209) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 201391 + ... + 202043.

It is an arithmetic number, because the mean of its divisors is an integer number (6330720).

Almost surely, 2^131721201 is an apocalyptic number.

It is an amenable number.

131721201 is a deficient number, since it is larger than the sum of its proper divisors (70861839).

131721201 is a wasteful number, since it uses less digits than its factorization.

131721201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 934 (or 928 counting only the distinct ones).

The product of its (nonzero) digits is 84, while the sum is 18.

The square root of 131721201 is about 11476.9857105426. The cubic root of 131721201 is about 508.8056133125.

Adding to 131721201 its reverse (102127131), we get a palindrome (233848332).

The spelling of 131721201 in words is "one hundred thirty-one million, seven hundred twenty-one thousand, two hundred one".