131221201129 has 4 divisors (see below), whose sum is σ = 131534378640. Its totient is φ = 130908023620.

The previous prime is 131221201123. The next prime is 131221201147. The reversal of 131221201129 is 921102122131.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 921102122131 = 44647 ⋅20630773.

It is a cyclic number.

It is not a de Polignac number, because 131221201129 - 2¹³ = 131221192937 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (131221201123) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 156588127 + ... + 156588964.

It is an arithmetic number, because the mean of its divisors is an integer number (32883594660).

Almost surely, 2^131221201129 is an apocalyptic number.

It is an amenable number.

131221201129 is a deficient number, since it is larger than the sum of its proper divisors (313177511).

131221201129 is an equidigital number, since it uses as much as digits as its factorization.

131221201129 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 313177510.

The product of its (nonzero) digits is 432, while the sum is 25.

The spelling of 131221201129 in words is "one hundred thirty-one billion, two hundred twenty-one million, two hundred one thousand, one hundred twenty-nine".