121121211012181 has 2 divisors, whose sum is σ = 121121211012182. Its totient is φ = 121121211012180.

The previous prime is 121121211012119. The next prime is 121121211012251. The reversal of 121121211012181 is 181210112121121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 89583215155281 + 31537995856900 = 9464841^2 + 5615870^2 .

It is an emirp because it is prime and its reverse (181210112121121) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121121211012181 is a prime.

It is a super-2 number, since 2×121121211012181² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121121211052181) 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, 60560605506090 + 60560605506091.

It is an arithmetic number, because the mean of its divisors is an integer number (60560605506091).

Almost surely, 2^{121121211012181} is an apocalyptic number.

It is an amenable number.

121121211012181 is a deficient number, since it is larger than the sum of its proper divisors (1).

121121211012181 is an equidigital number, since it uses as much as digits as its factorization.

121121211012181 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 128, while the sum is 25.

The spelling of 121121211012181 in words is "one hundred twenty-one trillion, one hundred twenty-one billion, two hundred eleven million, twelve thousand, one hundred eighty-one".