21211020202202 has 4 divisors (see below), whose sum is σ = 31816530303306. Its totient is φ = 10605510101100.

The previous prime is 21211020202171. The next prime is 21211020202259. The reversal of 21211020202202 is 20220202011212.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 21175265552281 + 35754649921 = 4601659^2 + 189089^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5302755050549 + ... + 5302755050552.

Almost surely, 2^{21211020202202} is an apocalyptic number.

21211020202202 is a deficient number, since it is larger than the sum of its proper divisors (10605510101104).

21211020202202 is a wasteful number, since it uses less digits than its factorization.

21211020202202 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10605510101103.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 21211020202202 its reverse (20220202011212), we get a palindrome (41431222213414).

The spelling of 21211020202202 in words is "twenty-one trillion, two hundred eleven billion, twenty million, two hundred two thousand, two hundred two".