111220001001 has 24 divisors (see below), whose sum is σ = 165830660424. Its totient is φ = 71776454400.

The previous prime is 111220000999. The next prime is 111220001003. The reversal of 111220001001 is 100100022111.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (111220000999) and next prime (111220001003).

It can be written as a sum of positive squares in 4 ways, for example, as 32400000000 + 78820001001 = 180000^2 + 280749^2 .

It is not a de Polignac number, because 111220001001 - 2¹ = 111220000999 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (111220001003) 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 in 23 ways as a sum of consecutive naturals, for example, 782100 + ... + 913301.

It is an arithmetic number, because the mean of its divisors is an integer number (6909610851).

Almost surely, 2^111220001001 is an apocalyptic number.

It is an amenable number.

111220001001 is a deficient number, since it is larger than the sum of its proper divisors (54610659423).

111220001001 is a wasteful number, since it uses less digits than its factorization.

111220001001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1695641 (or 1695638 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 111220001001 its reverse (100100022111), we get a palindrome (211320023112).

The spelling of 111220001001 in words is "one hundred eleven billion, two hundred twenty million, one thousand, one".