201221202122001 has 24 divisors (see below), whose sum is σ = 291024875310624. Its totient is φ = 133975785888000.

The previous prime is 201221202121987. The next prime is 201221202122009. The reversal of 201221202122001 is 100221202122102.

It is a happy number.

201221202122001 is a `hidden beast` number, since 20 + 1 + 221 + 202 + 1 + 220 + 0 + 1 = 666.

It is not a de Polignac number, because 201221202122001 - 2²⁵ = 201221168567569 is a prime.

It is not an unprimeable number, because it can be changed into a prime (201221202122009) 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, 105121665 + ... + 107018721.

It is an arithmetic number, because the mean of its divisors is an integer number (12126036471276).

Almost surely, 2^{201221202122001} is an apocalyptic number.

It is an amenable number.

201221202122001 is a deficient number, since it is larger than the sum of its proper divisors (89803673188623).

201221202122001 is a wasteful number, since it uses less digits than its factorization.

201221202122001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1912141 (or 1912138 counting only the distinct ones).

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

Adding to 201221202122001 its reverse (100221202122102), we get a palindrome (301442404244103).

The spelling of 201221202122001 in words is "two hundred one trillion, two hundred twenty-one billion, two hundred two million, one hundred twenty-two thousand, one".