111982721993 has 2 divisors, whose sum is σ = 111982721994. Its totient is φ = 111982721992.

The previous prime is 111982721933. The next prime is 111982721999. The reversal of 111982721993 is 399127289111.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 77330154889 + 34652567104 = 278083^2 + 186152^2 .

It is a cyclic number.

It is not a de Polignac number, because 111982721993 - 2⁸ = 111982721737 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (111982721999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55991360996 + 55991360997.

It is an arithmetic number, because the mean of its divisors is an integer number (55991360997).

Almost surely, 2^111982721993 is an apocalyptic number.

It is an amenable number.

111982721993 is a deficient number, since it is larger than the sum of its proper divisors (1).

111982721993 is an equidigital number, since it uses as much as digits as its factorization.

111982721993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 489888, while the sum is 53.

The spelling of 111982721993 in words is "one hundred eleven billion, nine hundred eighty-two million, seven hundred twenty-one thousand, nine hundred ninety-three".