121123131233521 has 2 divisors, whose sum is σ = 121123131233522. Its totient is φ = 121123131233520.

The previous prime is 121123131233483. The next prime is 121123131233551. The reversal of 121123131233521 is 125332131321121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 94149276333025 + 26973854900496 = 9703055^2 + 5193636^2 .

It is an emirp because it is prime and its reverse (125332131321121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 121123131233521 - 2¹⁹ = 121123130709233 is a prime.

It is not a weakly prime, because it can be changed into another prime (121123131233551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60561565616760 + 60561565616761.

It is an arithmetic number, because the mean of its divisors is an integer number (60561565616761).

Almost surely, 2^{121123131233521} is an apocalyptic number.

It is an amenable number.

121123131233521 is a deficient number, since it is larger than the sum of its proper divisors (1).

121123131233521 is an equidigital number, since it uses as much as digits as its factorization.

121123131233521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6480, while the sum is 31.

Adding to 121123131233521 its reverse (125332131321121), we get a palindrome (246455262554642).

The spelling of 121123131233521 in words is "one hundred twenty-one trillion, one hundred twenty-three billion, one hundred thirty-one million, two hundred thirty-three thousand, five hundred twenty-one".