111001001221221 has 64 divisors (see below), whose sum is σ = 154920436070400. Its totient is φ = 70631381673216.

The previous prime is 111001001221213. The next prime is 111001001221259. The reversal of 111001001221221 is 122122100100111.

It is a happy number.

It is not a de Polignac number, because 111001001221221 - 2³ = 111001001221213 is a prime.

It is a super-2 number, since 2×111001001221221² (a number of 29 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 111001001221221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111001001221211) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 8009301190 + ... + 8009315048.

It is an arithmetic number, because the mean of its divisors is an integer number (2420631813600).

Almost surely, 2^{111001001221221} is an apocalyptic number.

It is an amenable number.

111001001221221 is a deficient number, since it is larger than the sum of its proper divisors (43919434849179).

111001001221221 is a wasteful number, since it uses less digits than its factorization.

111001001221221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20538.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 111001001221221 its reverse (122122100100111), we get a palindrome (233123101321332).

The spelling of 111001001221221 in words is "one hundred eleven trillion, one billion, one million, two hundred twenty-one thousand, two hundred twenty-one".