221111121001 has 4 divisors (see below), whose sum is σ = 221136425604. Its totient is φ = 221085816400.

The previous prime is 221111120987. The next prime is 221111121013. The reversal of 221111121001 is 100121111122.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 32039210025 + 189071910976 = 178995^2 + 434824^2 .

It is a cyclic number.

It is not a de Polignac number, because 221111121001 - 2¹⁷ = 221110989929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221111191001) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12639190 + ... + 12656671.

It is an arithmetic number, because the mean of its divisors is an integer number (55284106401).

Almost surely, 2^221111121001 is an apocalyptic number.

It is an amenable number.

221111121001 is a deficient number, since it is larger than the sum of its proper divisors (25304603).

221111121001 is an equidigital number, since it uses as much as digits as its factorization.

221111121001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25304602.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 221111121001 its reverse (100121111122), we get a palindrome (321232232123).

The spelling of 221111121001 in words is "two hundred twenty-one billion, one hundred eleven million, one hundred twenty-one thousand, one".