21101220222201 has 48 divisors (see below), whose sum is σ = 36351583107840. Its totient is φ = 11532535470720.

The previous prime is 21101220222179. The next prime is 21101220222211. The reversal of 21101220222201 is 10222202210112.

It is a happy number.

21101220222201 is a `hidden beast` number, since 21 + 1 + 0 + 1 + 220 + 222 + 201 = 666.

It is not a de Polignac number, because 21101220222201 - 2³¹ = 21099072738553 is a prime.

It is a super-2 number, since 2×21101220222201² (a number of 27 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21101220222211) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 15381171 + ... + 16696791.

It is an arithmetic number, because the mean of its divisors is an integer number (757324648080).

Almost surely, 2^{21101220222201} is an apocalyptic number.

21101220222201 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21101220222201 is a deficient number, since it is larger than the sum of its proper divisors (15250362885639).

21101220222201 is a wasteful number, since it uses less digits than its factorization.

21101220222201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1326726 (or 1326723 counting only the distinct ones).

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

Adding to 21101220222201 its reverse (10222202210112), we get a palindrome (31323422432313).

The spelling of 21101220222201 in words is "twenty-one trillion, one hundred one billion, two hundred twenty million, two hundred twenty-two thousand, two hundred one".