122100100021 has 4 divisors (see below), whose sum is σ = 122129675500. Its totient is φ = 122070524544.

The previous prime is 122100099997. The next prime is 122100100027. The reversal of 122100100021 is 120001001221.

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 91499595121 + 30600504900 = 302489^2 + 174930^2 .

It is a cyclic number.

It is not a de Polignac number, because 122100100021 - 2¹³ = 122100091829 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 122100099980 and 122100100007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (122100100027) 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, 14781546 + ... + 14789803.

It is an arithmetic number, because the mean of its divisors is an integer number (30532418875).

Almost surely, 2^122100100021 is an apocalyptic number.

It is an amenable number.

122100100021 is a deficient number, since it is larger than the sum of its proper divisors (29575479).

122100100021 is an equidigital number, since it uses as much as digits as its factorization.

122100100021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29575478.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 122100100021 its reverse (120001001221), we get a palindrome (242101101242).

The spelling of 122100100021 in words is "one hundred twenty-two billion, one hundred million, one hundred thousand, twenty-one".