202120121220121 has 4 divisors (see below), whose sum is σ = 217667822852452. Its totient is φ = 186572419587792.

The previous prime is 202120121220103. The next prime is 202120121220133. The reversal of 202120121220121 is 121022121021202.

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 38411039056896 + 163709082163225 = 6197664^2 + 12794885^2 .

It is a cyclic number.

It is not a de Polignac number, because 202120121220121 - 2¹⁵ = 202120121187353 is a prime.

It is a super-4 number, since 4×202120121220121⁴ (a number of 58 digits) contains 4444 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (202120121220181) 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, 7773850816146 + ... + 7773850816171.

It is an arithmetic number, because the mean of its divisors is an integer number (54416955713113).

Almost surely, 2^{202120121220121} is an apocalyptic number.

It is an amenable number.

202120121220121 is a deficient number, since it is larger than the sum of its proper divisors (15547701632331).

202120121220121 is a wasteful number, since it uses less digits than its factorization.

202120121220121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15547701632330.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 202120121220121 its reverse (121022121021202), we get a palindrome (323142242241323).

The spelling of 202120121220121 in words is "two hundred two trillion, one hundred twenty billion, one hundred twenty-one million, two hundred twenty thousand, one hundred twenty-one".