21110122001 has 4 divisors (see below), whose sum is σ = 21112208100. Its totient is φ = 21108035904.

The previous prime is 21110121983. The next prime is 21110122003. The reversal of 21110122001 is 10022101112.

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 9249822976 + 11860299025 = 96176^2 + 108905^2 .

It is a cyclic number.

It is not a de Polignac number, because 21110122001 - 2⁶ = 21110121937 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21110122003) 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, 1027796 + ... + 1048133.

It is an arithmetic number, because the mean of its divisors is an integer number (5278052025).

Almost surely, 2^21110122001 is an apocalyptic number.

It is an amenable number.

21110122001 is a deficient number, since it is larger than the sum of its proper divisors (2086099).

21110122001 is a wasteful number, since it uses less digits than its factorization.

21110122001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2086098.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21110122001 its reverse (10022101112), we get a palindrome (31132223113).

The spelling of 21110122001 in words is "twenty-one billion, one hundred ten million, one hundred twenty-two thousand, one".