1981299219911 has 16 divisors (see below), whose sum is σ = 2171466001440. Its totient is φ = 1792811642880.

The previous prime is 1981299219901. The next prime is 1981299219917. The reversal of 1981299219911 is 1199129921891.

It is a cyclic number.

It is not a de Polignac number, because 1981299219911 - 2¹⁸ = 1981298957767 is a prime.

It is a super-3 number, since 3×1981299219911³ (a number of 38 digits) contains 333 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 (1981299219917) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9002495 + ... + 9219951.

It is an arithmetic number, because the mean of its divisors is an integer number (135716625090).

Almost surely, 2^{1981299219911} is an apocalyptic number.

1981299219911 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1981299219911 is a deficient number, since it is larger than the sum of its proper divisors (190166781529).

1981299219911 is a wasteful number, since it uses less digits than its factorization.

1981299219911 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 221314.

The product of its digits is 1889568, while the sum is 62.

The spelling of 1981299219911 in words is "one trillion, nine hundred eighty-one billion, two hundred ninety-nine million, two hundred nineteen thousand, nine hundred eleven".