1221012231121 has 2 divisors, whose sum is σ = 1221012231122. Its totient is φ = 1221012231120.

The previous prime is 1221012231097. The next prime is 1221012231139. The reversal of 1221012231121 is 1211322101221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 987312500496 + 233699730625 = 993636^2 + 483425^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221012231121 - 2⁷ = 1221012230993 is a prime.

It is not a weakly prime, because it can be changed into another prime (1221012231151) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610506115560 + 610506115561.

It is an arithmetic number, because the mean of its divisors is an integer number (610506115561).

Almost surely, 2^{1221012231121} is an apocalyptic number.

It is an amenable number.

1221012231121 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221012231121 is an equidigital number, since it uses as much as digits as its factorization.

1221012231121 is an evil number, because the sum of its binary digits is even.

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

Adding to 1221012231121 its reverse (1211322101221), we get a palindrome (2432334332342).

The spelling of 1221012231121 in words is "one trillion, two hundred twenty-one billion, twelve million, two hundred thirty-one thousand, one hundred twenty-one".