131231320221 has 16 divisors (see below), whose sum is σ = 176541778944. Its totient is φ = 86704364544.

The previous prime is 131231320177. The next prime is 131231320247. The reversal of 131231320221 is 122023132131.

It is not a de Polignac number, because 131231320221 - 2¹¹ = 131231318173 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131231340221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5563765 + ... + 5587301.

It is an arithmetic number, because the mean of its divisors is an integer number (11033861184).

Almost surely, 2^131231320221 is an apocalyptic number.

It is an amenable number.

131231320221 is a deficient number, since it is larger than the sum of its proper divisors (45310458723).

131231320221 is a wasteful number, since it uses less digits than its factorization.

131231320221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40100.

The product of its (nonzero) digits is 432, while the sum is 21.

Adding to 131231320221 its reverse (122023132131), we get a palindrome (253254452352).

The spelling of 131231320221 in words is "one hundred thirty-one billion, two hundred thirty-one million, three hundred twenty thousand, two hundred twenty-one".