131211210121 has 4 divisors (see below), whose sum is σ = 132212822544. Its totient is φ = 130209597700.

The previous prime is 131211210089. The next prime is 131211210131. The reversal of 131211210121 is 121012112131.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 131211210121 - 2⁵ = 131211210089 is a prime.

It is a super-2 number, since 2×131211210121² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 131211210095 and 131211210104.

It is not an unprimeable number, because it can be changed into a prime (131211210131) 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, 500806015 + ... + 500806276.

It is an arithmetic number, because the mean of its divisors is an integer number (33053205636).

Almost surely, 2^131211210121 is an apocalyptic number.

It is an amenable number.

131211210121 is a deficient number, since it is larger than the sum of its proper divisors (1001612423).

131211210121 is a wasteful number, since it uses less digits than its factorization.

131211210121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1001612422.

The product of its (nonzero) digits is 24, while the sum is 16.

Adding to 131211210121 its reverse (121012112131), we get a palindrome (252223322252).

The spelling of 131211210121 in words is "one hundred thirty-one billion, two hundred eleven million, two hundred ten thousand, one hundred twenty-one".