100001201021221 has 4 divisors (see below), whose sum is σ = 100002006431244. Its totient is φ = 100000395611200.

The previous prime is 100001201021213. The next prime is 100001201021231. The reversal of 100001201021221 is 122120102100001.

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 68464272170596 + 31536928850625 = 8274314^2 + 5615775^2 .

It is a cyclic number.

It is not a de Polignac number, because 100001201021221 - 2³ = 100001201021213 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100001201021231) 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, 402518740 + ... + 402767101.

It is an arithmetic number, because the mean of its divisors is an integer number (25000501607811).

Almost surely, 2^{100001201021221} is an apocalyptic number.

It is an amenable number.

100001201021221 is a deficient number, since it is larger than the sum of its proper divisors (805410023).

100001201021221 is an equidigital number, since it uses as much as digits as its factorization.

100001201021221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 805410022.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 100001201021221 its reverse (122120102100001), we get a palindrome (222121303121222).

The spelling of 100001201021221 in words is "one hundred trillion, one billion, two hundred one million, twenty-one thousand, two hundred twenty-one".