111091821593 has 2 divisors, whose sum is σ = 111091821594. Its totient is φ = 111091821592.

The previous prime is 111091821571. The next prime is 111091821647. The reversal of 111091821593 is 395128190111.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 71485647424 + 39606174169 = 267368^2 + 199013^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-111091821593 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 111091821593.

It is not a weakly prime, because it can be changed into another prime (111091821793) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55545910796 + 55545910797.

It is an arithmetic number, because the mean of its divisors is an integer number (55545910797).

Almost surely, 2^111091821593 is an apocalyptic number.

It is an amenable number.

111091821593 is a deficient number, since it is larger than the sum of its proper divisors (1).

111091821593 is an equidigital number, since it uses as much as digits as its factorization.

111091821593 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 19440, while the sum is 41.

The spelling of 111091821593 in words is "one hundred eleven billion, ninety-one million, eight hundred twenty-one thousand, five hundred ninety-three".