1981124269 has 2 divisors, whose sum is σ = 1981124270. Its totient is φ = 1981124268.

The previous prime is 1981124219. The next prime is 1981124287. The reversal of 1981124269 is 9624211891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1197852100 + 783272169 = 34610^2 + 27987^2 .

It is a cyclic number.

It is not a de Polignac number, because 1981124269 - 2¹⁹ = 1980599981 is a prime.

It is a super-2 number, since 2×1981124269² = 7849706738441568722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1981124219) 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, 990562134 + 990562135.

It is an arithmetic number, because the mean of its divisors is an integer number (990562135).

Almost surely, 2^1981124269 is an apocalyptic number.

It is an amenable number.

1981124269 is a deficient number, since it is larger than the sum of its proper divisors (1).

1981124269 is an equidigital number, since it uses as much as digits as its factorization.

1981124269 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 62208, while the sum is 43.

The square root of 1981124269 is about 44509.8221632035. The cubic root of 1981124269 is about 1255.9448594821.

The spelling of 1981124269 in words is "one billion, nine hundred eighty-one million, one hundred twenty-four thousand, two hundred sixty-nine".