21220111010201 has 12 divisors (see below), whose sum is σ = 22180479947820. Its totient is φ = 20277162339840.

The previous prime is 21220111010149. The next prime is 21220111010269. The reversal of 21220111010201 is 10201011102212.

It can be written as a sum of positive squares in 6 ways, for example, as 2380691616601 + 18839419393600 = 1542949^2 + 4340440^2 .

It is a de Polignac number, because none of the positive numbers 2^k-21220111010201 is a prime.

It is a super-2 number, since 2×21220111010201² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21220111010101) 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, 38611610 + ... + 39157331.

It is an arithmetic number, because the mean of its divisors is an integer number (1848373328985).

Almost surely, 2^{21220111010201} is an apocalyptic number.

It is an amenable number.

21220111010201 is a deficient number, since it is larger than the sum of its proper divisors (960368937619).

21220111010201 is an frugal number, since it uses more digits than its factorization.

21220111010201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77769164 (or 77769067 counting only the distinct ones).

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

Adding to 21220111010201 its reverse (10201011102212), we get a palindrome (31421122112413).

The spelling of 21220111010201 in words is "twenty-one trillion, two hundred twenty billion, one hundred eleven million, ten thousand, two hundred one".