121213031813 has 2 divisors, whose sum is σ = 121213031814. Its totient is φ = 121213031812.

The previous prime is 121213031809. The next prime is 121213031827. The reversal of 121213031813 is 318130312121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 94776548164 + 26436483649 = 307858^2 + 162593^2 .

It is a cyclic number.

It is not a de Polignac number, because 121213031813 - 2² = 121213031809 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121213031833) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60606515906 + 60606515907.

It is an arithmetic number, because the mean of its divisors is an integer number (60606515907).

Almost surely, 2^121213031813 is an apocalyptic number.

It is an amenable number.

121213031813 is a deficient number, since it is larger than the sum of its proper divisors (1).

121213031813 is an equidigital number, since it uses as much as digits as its factorization.

121213031813 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 864, while the sum is 26.

Adding to 121213031813 its reverse (318130312121), we get a palindrome (439343343934).

The spelling of 121213031813 in words is "one hundred twenty-one billion, two hundred thirteen million, thirty-one thousand, eight hundred thirteen".