111221001209 has 2 divisors, whose sum is σ = 111221001210. Its totient is φ = 111221001208.

The previous prime is 111221001187. The next prime is 111221001211. The reversal of 111221001209 is 902100122111.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 79215791209 + 32005210000 = 281453^2 + 178900^2 .

It is a cyclic number.

It is not a de Polignac number, because 111221001209 - 2⁸ = 111221000953 is a prime.

It is a super-2 number, since 2×111221001209² (a number of 23 digits) contains 22 as substring.

Together with 111221001211, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (111221001239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55610500604 + 55610500605.

It is an arithmetic number, because the mean of its divisors is an integer number (55610500605).

Almost surely, 2^111221001209 is an apocalyptic number.

It is an amenable number.

111221001209 is a deficient number, since it is larger than the sum of its proper divisors (1).

111221001209 is an equidigital number, since it uses as much as digits as its factorization.

111221001209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72, while the sum is 20.

The spelling of 111221001209 in words is "one hundred eleven billion, two hundred twenty-one million, one thousand, two hundred nine".