20201000111221 has 2 divisors, whose sum is σ = 20201000111222. Its totient is φ = 20201000111220.

The previous prime is 20201000111209. The next prime is 20201000111239. The reversal of 20201000111221 is 12211100010202.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11885332095121 + 8315668016100 = 3447511^2 + 2883690^2 .

It is a cyclic number.

It is not a de Polignac number, because 20201000111221 - 2¹³ = 20201000103029 is a prime.

It is a super-2 number, since 2×20201000111221² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20201000111291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10100500055610 + 10100500055611.

It is an arithmetic number, because the mean of its divisors is an integer number (10100500055611).

Almost surely, 2^{20201000111221} is an apocalyptic number.

It is an amenable number.

20201000111221 is a deficient number, since it is larger than the sum of its proper divisors (1).

20201000111221 is an equidigital number, since it uses as much as digits as its factorization.

20201000111221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 20201000111221 its reverse (12211100010202), we get a palindrome (32412100121423).

The spelling of 20201000111221 in words is "twenty trillion, two hundred one billion, one hundred eleven thousand, two hundred twenty-one".