21012102202122 has 20 divisors (see below), whose sum is σ = 47082673453266. Its totient is φ = 7004034067320.

The previous prime is 21012102202111. The next prime is 21012102202129. The reversal of 21012102202122 is 22120220121012.

It is a happy number.

21012102202122 is a `hidden beast` number, since 21 + 0 + 1 + 210 + 220 + 212 + 2 = 666.

It can be written as a sum of positive squares in only one way, i.e., 21001313432961 + 10788769161 = 4582719^2 + 103869^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 21012102202095 and 21012102202104.

It is not an unprimeable number, because it can be changed into a prime (21012102202129) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 64852167129 + ... + 64852167452.

Almost surely, 2^{21012102202122} is an apocalyptic number.

21012102202122 is an abundant number, since it is smaller than the sum of its proper divisors (26070571251144).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21012102202122 is a wasteful number, since it uses less digits than its factorization.

21012102202122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129704334595 (or 129704334586 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 21012102202122 its reverse (22120220121012), we get a palindrome (43132322323134).

The spelling of 21012102202122 in words is "twenty-one trillion, twelve billion, one hundred two million, two hundred two thousand, one hundred twenty-two".