20201111221 has 4 divisors (see below), whose sum is σ = 20202825952. Its totient is φ = 20199396492.

The previous prime is 20201111207. The next prime is 20201111323. The reversal of 20201111221 is 12211110202.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12211110202 = 2 ⋅6105555101.

It is a cyclic number.

It is not a de Polignac number, because 20201111221 - 2²⁷ = 20066893493 is a prime.

It is a super-2 number, since 2×20201111221² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20201111521) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 839571 + ... + 863296.

It is an arithmetic number, because the mean of its divisors is an integer number (5050706488).

Almost surely, 2^20201111221 is an apocalyptic number.

It is an amenable number.

20201111221 is a deficient number, since it is larger than the sum of its proper divisors (1714731).

20201111221 is a wasteful number, since it uses less digits than its factorization.

20201111221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1714730.

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

Adding to 20201111221 its reverse (12211110202), we get a palindrome (32412221423).

The spelling of 20201111221 in words is "twenty billion, two hundred one million, one hundred eleven thousand, two hundred twenty-one".