202021012021221 has 6 divisors (see below), whose sum is σ = 291808128475110. Its totient is φ = 134680674680808.

The previous prime is 202021012021217. The next prime is 202021012021249. The reversal of 202021012021221 is 122120210120202.

It is a happy number.

202021012021221 is a `hidden beast` number, since 202 + 0 + 210 + 1 + 20 + 212 + 21 = 666.

It can be written as a sum of positive squares in only one way, i.e., 111009698220996 + 91011313800225 = 10536114^2 + 9539985^2 .

It is not a de Polignac number, because 202021012021221 - 2² = 202021012021217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 202021012021194 and 202021012021203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (202021012021201) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 11223389556726 + ... + 11223389556743.

It is an arithmetic number, because the mean of its divisors is an integer number (48634688079185).

Almost surely, 2^{202021012021221} is an apocalyptic number.

It is an amenable number.

202021012021221 is a deficient number, since it is larger than the sum of its proper divisors (89787116453889).

202021012021221 is a wasteful number, since it uses less digits than its factorization.

202021012021221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22446779113475 (or 22446779113472 counting only the distinct ones).

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

Adding to 202021012021221 its reverse (122120210120202), we get a palindrome (324141222141423).

The spelling of 202021012021221 in words is "two hundred two trillion, twenty-one billion, twelve million, twenty-one thousand, two hundred twenty-one".