111221001091 has 2 divisors, whose sum is σ = 111221001092. Its totient is φ = 111221001090.

The previous prime is 111221001049. The next prime is 111221001109. The reversal of 111221001091 is 190100122111.

Together with next prime (111221001109) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 111221001091 - 2¹⁵ = 111220968323 is a prime.

It is a super-2 number, since 2×111221001091² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (111221007091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55610500545 + 55610500546.

It is an arithmetic number, because the mean of its divisors is an integer number (55610500546).

Almost surely, 2^111221001091 is an apocalyptic number.

111221001091 is a deficient number, since it is larger than the sum of its proper divisors (1).

111221001091 is an equidigital number, since it uses as much as digits as its factorization.

111221001091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36, while the sum is 19.

The spelling of 111221001091 in words is "one hundred eleven billion, two hundred twenty-one million, one thousand, ninety-one".