1912789198081 has 2 divisors, whose sum is σ = 1912789198082. Its totient is φ = 1912789198080.

The previous prime is 1912789198051. The next prime is 1912789198097. The reversal of 1912789198081 is 1808919872191.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1906652825856 + 6136372225 = 1380816^2 + 78335^2 .

It is a cyclic number.

It is not a de Polignac number, because 1912789198081 - 2³⁵ = 1878429459713 is a prime.

It is a super-2 number, since 2×1912789198081² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1912789198051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 956394599040 + 956394599041.

It is an arithmetic number, because the mean of its divisors is an integer number (956394599041).

Almost surely, 2^{1912789198081} is an apocalyptic number.

It is an amenable number.

1912789198081 is a deficient number, since it is larger than the sum of its proper divisors (1).

1912789198081 is an equidigital number, since it uses as much as digits as its factorization.

1912789198081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5225472, while the sum is 64.

The spelling of 1912789198081 in words is "one trillion, nine hundred twelve billion, seven hundred eighty-nine million, one hundred ninety-eight thousand, eighty-one".