12012199981 has 4 divisors (see below), whose sum is σ = 12267778752. Its totient is φ = 11756621212.

The previous prime is 12012199933. The next prime is 12012200029. The reversal of 12012199981 is 18999121021.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18999121021 = 971 ⋅19566551.

It is an interprime number because it is at equal distance from previous prime (12012199933) and next prime (12012200029).

It is a cyclic number.

It is not a de Polignac number, because 12012199981 - 2¹¹ = 12012197933 is a prime.

It is a super-2 number, since 2×12012199981² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12012199181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 127789315 + ... + 127789408.

It is an arithmetic number, because the mean of its divisors is an integer number (3066944688).

Almost surely, 2^12012199981 is an apocalyptic number.

It is an amenable number.

12012199981 is a deficient number, since it is larger than the sum of its proper divisors (255578771).

12012199981 is an equidigital number, since it uses as much as digits as its factorization.

12012199981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255578770.

The product of its (nonzero) digits is 23328, while the sum is 43.

The spelling of 12012199981 in words is "twelve billion, twelve million, one hundred ninety-nine thousand, nine hundred eighty-one".