202121101021121 has 4 divisors (see below), whose sum is σ = 202409433548244. Its totient is φ = 201832768494000.

The previous prime is 202121101021117. The next prime is 202121101021127. The reversal of 202121101021121 is 121120101121202.

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

It can be written as a sum of positive squares in 2 ways, for example, as 114826462235521 + 87294638785600 = 10715711^2 + 9343160^2 .

It is a cyclic number.

It is not a de Polignac number, because 202121101021121 - 2² = 202121101021117 is a prime.

It is a super-3 number, since 3×202121101021121³ (a number of 44 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 202121101021121.

It is not an unprimeable number, because it can be changed into a prime (202121101021127) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 144166262510 + ... + 144166263911.

It is an arithmetic number, because the mean of its divisors is an integer number (50602358387061).

Almost surely, 2^{202121101021121} is an apocalyptic number.

It is an amenable number.

202121101021121 is a deficient number, since it is larger than the sum of its proper divisors (288332527123).

202121101021121 is an equidigital number, since it uses as much as digits as its factorization.

202121101021121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 288332527122.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 202121101021121 its reverse (121120101121202), we get a palindrome (323241202142323).

The spelling of 202121101021121 in words is "two hundred two trillion, one hundred twenty-one billion, one hundred one million, twenty-one thousand, one hundred twenty-one".