1221010122121 has 2 divisors, whose sum is σ = 1221010122122. Its totient is φ = 1221010122120.

The previous prime is 1221010122067. The next prime is 1221010122133. The reversal of 1221010122121 is 1212210101221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1218791712121 + 2218410000 = 1103989^2 + 47100^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221010122121 - 2²¹ = 1221008024969 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1221010122095 and 1221010122104.

It is not a weakly prime, because it can be changed into another prime (1221010126121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610505061060 + 610505061061.

It is an arithmetic number, because the mean of its divisors is an integer number (610505061061).

Almost surely, 2^{1221010122121} is an apocalyptic number.

It is an amenable number.

1221010122121 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221010122121 is an equidigital number, since it uses as much as digits as its factorization.

1221010122121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 1221010122121 its reverse (1212210101221), we get a palindrome (2433220223342).

The spelling of 1221010122121 in words is "one trillion, two hundred twenty-one billion, ten million, one hundred twenty-two thousand, one hundred twenty-one".