21201100121201 has 24 divisors (see below), whose sum is σ = 28681462861632. Its totient is φ = 15249542536800.

The previous prime is 21201100121183. The next prime is 21201100121203. The reversal of 21201100121201 is 10212100110212.

It is not a de Polignac number, because 21201100121201 - 2²² = 21201095926897 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21201100121203) 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, 962712635 + ... + 962734656.

It is an arithmetic number, because the mean of its divisors is an integer number (1195060952568).

Almost surely, 2^{21201100121201} is an apocalyptic number.

It is an amenable number.

21201100121201 is a deficient number, since it is larger than the sum of its proper divisors (7480362740431).

21201100121201 is a wasteful number, since it uses less digits than its factorization.

21201100121201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1925447333 (or 1925447322 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21201100121201 its reverse (10212100110212), we get a palindrome (31413200231413).

The spelling of 21201100121201 in words is "twenty-one trillion, two hundred one billion, one hundred million, one hundred twenty-one thousand, two hundred one".