21001221102202 has 24 divisors (see below), whose sum is σ = 34626346282836. Its totient is φ = 9545908680000.

The previous prime is 21001221102193. The next prime is 21001221102233. The reversal of 21001221102202 is 20220112210012.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 13965311006361 + 7035910095841 = 3737019^2 + 2652529^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 25513302 + ... + 26323582.

Almost surely, 2^{21001221102202} is an apocalyptic number.

21001221102202 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21001221102202 is a deficient number, since it is larger than the sum of its proper divisors (13625125180634).

21001221102202 is a wasteful number, since it uses less digits than its factorization.

21001221102202 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 917406 (or 917395 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21001221102202 its reverse (20220112210012), we get a palindrome (41221333312214).

The spelling of 21001221102202 in words is "twenty-one trillion, one billion, two hundred twenty-one million, one hundred two thousand, two hundred two".