1212101331221 has 4 divisors (see below), whose sum is σ = 1322292361344. Its totient is φ = 1101910301100.

The previous prime is 1212101331211. The next prime is 1212101331289. The reversal of 1212101331221 is 1221331012121.

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 1212101331221 - 2¹⁸ = 1212101069077 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1212101331193 and 1212101331202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212101331211) 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, 55095515045 + ... + 55095515066.

It is an arithmetic number, because the mean of its divisors is an integer number (330573090336).

Almost surely, 2^{1212101331221} is an apocalyptic number.

1212101331221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1212101331221 is a deficient number, since it is larger than the sum of its proper divisors (110191030123).

1212101331221 is a wasteful number, since it uses less digits than its factorization.

1212101331221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110191030122.

The product of its (nonzero) digits is 144, while the sum is 20.

Adding to 1212101331221 its reverse (1221331012121), we get a palindrome (2433432343342).

The spelling of 1212101331221 in words is "one trillion, two hundred twelve billion, one hundred one million, three hundred thirty-one thousand, two hundred twenty-one".