202121212122 has 48 divisors (see below), whose sum is σ = 463726022760. Its totient is φ = 63405628416.

The previous prime is 202121212121. The next prime is 202121212129. The reversal of 202121212122 is 221212121202.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 165444749001 + 36676463121 = 406749^2 + 191511^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 202121212095 and 202121212104.

It is not an unprimeable number, because it can be changed into a prime (202121212121) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7290078 + ... + 7317750.

Almost surely, 2^202121212122 is an apocalyptic number.

202121212122 is an abundant number, since it is smaller than the sum of its proper divisors (261604810638).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

202121212122 is a wasteful number, since it uses less digits than its factorization.

202121212122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51567 (or 51564 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 202121212122 its reverse (221212121202), we get a palindrome (423333333324).

The spelling of 202121212122 in words is "two hundred two billion, one hundred twenty-one million, two hundred twelve thousand, one hundred twenty-two".