201222212121 has 96 divisors (see below), whose sum is σ = 365862002688. Its totient is φ = 107888267520.

The previous prime is 201222212057. The next prime is 201222212123. The reversal of 201222212121 is 121212222102.

It is a happy number.

It is not a de Polignac number, because 201222212121 - 2⁶ = 201222212057 is a prime.

201222212121 is a modest number, since divided by 212121 gives 201222 as remainder.

It is a junction number, because it is equal to n+sod(n) for n = 201222212094 and 201222212103.

It is not an unprimeable number, because it can be changed into a prime (201222212123) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 9561016 + ... + 9582038.

It is an arithmetic number, because the mean of its divisors is an integer number (3811062528).

Almost surely, 2^201222212121 is an apocalyptic number.

201222212121 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

201222212121 is a deficient number, since it is larger than the sum of its proper divisors (164639790567).

201222212121 is a wasteful number, since it uses less digits than its factorization.

201222212121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21393 (or 21381 counting only the distinct ones).

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

Adding to 201222212121 its reverse (121212222102), we get a palindrome (322434434223).

The spelling of 201222212121 in words is "two hundred one billion, two hundred twenty-two million, two hundred twelve thousand, one hundred twenty-one".