201221122221 has 12 divisors (see below), whose sum is σ = 332174551072. Its totient is φ = 114983498376.

The previous prime is 201221122213. The next prime is 201221122261. The reversal of 201221122221 is 122221122102.

It is a happy number.

201221122221 is a `hidden beast` number, since 201 + 221 + 1 + 22 + 221 = 666.

It is not a de Polignac number, because 201221122221 - 2³ = 201221122213 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 201221122194 and 201221122203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201221122261) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1596992971 + ... + 1596993096.

Almost surely, 2^201221122221 is an apocalyptic number.

201221122221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

201221122221 is a deficient number, since it is larger than the sum of its proper divisors (130953428851).

201221122221 is a wasteful number, since it uses less digits than its factorization.

201221122221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3193986080 (or 3193986077 counting only the distinct ones).

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

Adding to 201221122221 its reverse (122221122102), we get a palindrome (323442244323).

The spelling of 201221122221 in words is "two hundred one billion, two hundred twenty-one million, one hundred twenty-two thousand, two hundred twenty-one".