111221123209 has 12 divisors (see below), whose sum is σ = 129386654100. Its totient is φ = 95327248128.

The previous prime is 111221123191. The next prime is 111221123249. The reversal of 111221123209 is 902321122111.

It can be written as a sum of positive squares in 2 ways, for example, as 15838977609 + 95382145600 = 125853^2 + 308840^2 .

It is not a de Polignac number, because 111221123209 - 2⁷ = 111221123081 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (111221123249) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1065837 + ... + 1165525.

It is an arithmetic number, because the mean of its divisors is an integer number (10782221175).

Almost surely, 2^111221123209 is an apocalyptic number.

It is an amenable number.

111221123209 is a deficient number, since it is larger than the sum of its proper divisors (18165530891).

111221123209 is an equidigital number, since it uses as much as digits as its factorization.

111221123209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122472 (or 122465 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 25.

The spelling of 111221123209 in words is "one hundred eleven billion, two hundred twenty-one million, one hundred twenty-three thousand, two hundred nine".