1312221210121 has 4 divisors (see below), whose sum is σ = 1336980100932. Its totient is φ = 1287462319312.

The previous prime is 1312221210101. The next prime is 1312221210127. The reversal of 1312221210121 is 1210121222131.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 546211161721 + 766010048400 = 739061^2 + 875220^2 .

It is a cyclic number.

It is not a de Polignac number, because 1312221210121 - 2⁷ = 1312221209993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1312221210127) 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, 12379445326 + ... + 12379445431.

It is an arithmetic number, because the mean of its divisors is an integer number (334245025233).

Almost surely, 2^{1312221210121} is an apocalyptic number.

It is an amenable number.

1312221210121 is a deficient number, since it is larger than the sum of its proper divisors (24758890811).

1312221210121 is an equidigital number, since it uses as much as digits as its factorization.

1312221210121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24758890810.

The product of its (nonzero) digits is 96, while the sum is 19.

Adding to 1312221210121 its reverse (1210121222131), we get a palindrome (2522342432252).

The spelling of 1312221210121 in words is "one trillion, three hundred twelve billion, two hundred twenty-one million, two hundred ten thousand, one hundred twenty-one".