1212012209981 has 2 divisors, whose sum is σ = 1212012209982. Its totient is φ = 1212012209980.

The previous prime is 1212012209971. The next prime is 1212012210037. The reversal of 1212012209981 is 1899022102121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 667170408025 + 544841801956 = 816805^2 + 738134^2 .

It is an emirp because it is prime and its reverse (1899022102121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1212012209981 - 2³⁸ = 937134303037 is a prime.

It is a super-2 number, since 2×1212012209981² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1212012209921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 606006104990 + 606006104991.

It is an arithmetic number, because the mean of its divisors is an integer number (606006104991).

Almost surely, 2^{1212012209981} is an apocalyptic number.

It is an amenable number.

1212012209981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1212012209981 is an equidigital number, since it uses as much as digits as its factorization.

1212012209981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10368, while the sum is 38.

The spelling of 1212012209981 in words is "one trillion, two hundred twelve billion, twelve million, two hundred nine thousand, nine hundred eighty-one".