202121021117 has 2 divisors, whose sum is σ = 202121021118. Its totient is φ = 202121021116.

The previous prime is 202121021087. The next prime is 202121021119. The reversal of 202121021117 is 711120121202.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 159643398916 + 42477622201 = 399554^2 + 206101^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-202121021117 is a prime.

Together with 202121021119, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (202121021119) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 101060510558 + 101060510559.

It is an arithmetic number, because the mean of its divisors is an integer number (101060510559).

Almost surely, 2^202121021117 is an apocalyptic number.

It is an amenable number.

202121021117 is a deficient number, since it is larger than the sum of its proper divisors (1).

202121021117 is an equidigital number, since it uses as much as digits as its factorization.

202121021117 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 112, while the sum is 20.

Adding to 202121021117 its reverse (711120121202), we get a palindrome (913241142319).

The spelling of 202121021117 in words is "two hundred two billion, one hundred twenty-one million, twenty-one thousand, one hundred seventeen".