21200220122 has 16 divisors (see below), whose sum is σ = 31916279880. Its totient is φ = 10561493568.

The previous prime is 21200220113. The next prime is 21200220131. The reversal of 21200220122 is 22102200212.

It is an interprime number because it is at equal distance from previous prime (21200220113) and next prime (21200220131).

It can be written as a sum of positive squares in 4 ways, for example, as 9934308241 + 11265911881 = 99671^2 + 106141^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21200220097 and 21200220106.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1507628 + ... + 1521624.

Almost surely, 2^21200220122 is an apocalyptic number.

21200220122 is a deficient number, since it is larger than the sum of its proper divisors (10716059758).

21200220122 is a wasteful number, since it uses less digits than its factorization.

21200220122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16705.

The product of its (nonzero) digits is 64, while the sum is 14.

Adding to 21200220122 its reverse (22102200212), we get a palindrome (43302420334).

The spelling of 21200220122 in words is "twenty-one billion, two hundred million, two hundred twenty thousand, one hundred twenty-two".