202221019981 has 2 divisors, whose sum is σ = 202221019982. Its totient is φ = 202221019980.

The previous prime is 202221019961. The next prime is 202221019997. The reversal of 202221019981 is 189910122202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 174753261225 + 27467758756 = 418035^2 + 165734^2 .

It is a cyclic number.

It is not a de Polignac number, because 202221019981 - 2³⁷ = 64782066509 is a prime.

It is a super-2 number, since 2×202221019981² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 202221019981.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (202221019901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 101110509990 + 101110509991.

It is an arithmetic number, because the mean of its divisors is an integer number (101110509991).

Almost surely, 2^202221019981 is an apocalyptic number.

It is an amenable number.

202221019981 is a deficient number, since it is larger than the sum of its proper divisors (1).

202221019981 is an equidigital number, since it uses as much as digits as its factorization.

202221019981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10368, while the sum is 37.

The spelling of 202221019981 in words is "two hundred two billion, two hundred twenty-one million, nineteen thousand, nine hundred eighty-one".