202122121021 has 8 divisors (see below), whose sum is σ = 202291479864. Its totient is φ = 201952819200.

The previous prime is 202122121009. The next prime is 202122121037. The reversal of 202122121021 is 120121221202.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 108234420100 + 93887700921 = 328990^2 + 306411^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-202122121021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 202122120986 and 202122121004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (202122121921) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9680425 + ... + 9701281.

It is an arithmetic number, because the mean of its divisors is an integer number (25286434983).

Almost surely, 2^202122121021 is an apocalyptic number.

It is an amenable number.

202122121021 is a deficient number, since it is larger than the sum of its proper divisors (169358843).

202122121021 is a wasteful number, since it uses less digits than its factorization.

202122121021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28511.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 202122121021 its reverse (120121221202), we get a palindrome (322243342223).

The spelling of 202122121021 in words is "two hundred two billion, one hundred twenty-two million, one hundred twenty-one thousand, twenty-one".