111221102100021 has 64 divisors (see below), whose sum is σ = 155228449259520. Its totient is φ = 70770714094080.

The previous prime is 111221102099917. The next prime is 111221102100113. The reversal of 111221102100021 is 120001201122111.

It is a happy number.

It is not a de Polignac number, because 111221102100021 - 2⁷ = 111221102099893 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111221102102021) 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, 945932166 + ... + 946049736.

It is an arithmetic number, because the mean of its divisors is an integer number (2425444519680).

Almost surely, 2^{111221102100021} is an apocalyptic number.

It is an amenable number.

111221102100021 is a deficient number, since it is larger than the sum of its proper divisors (44007347159499).

111221102100021 is a wasteful number, since it uses less digits than its factorization.

111221102100021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118386.

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

Adding to 111221102100021 its reverse (120001201122111), we get a palindrome (231222303222132).

The spelling of 111221102100021 in words is "one hundred eleven trillion, two hundred twenty-one billion, one hundred two million, one hundred thousand, twenty-one".