20011112221 has 4 divisors (see below), whose sum is σ = 20292958944. Its totient is φ = 19729265500.

The previous prime is 20011112207. The next prime is 20011112263. The reversal of 20011112221 is 12221111002.

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.

It is a cyclic number.

It is not a de Polignac number, because 20011112221 - 2¹⁵ = 20011079453 is a prime.

It is a super-2 number, since 2×20011112221² (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 (20011112521) 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, 140923255 + ... + 140923396.

It is an arithmetic number, because the mean of its divisors is an integer number (5073239736).

Almost surely, 2^20011112221 is an apocalyptic number.

It is an amenable number.

20011112221 is a deficient number, since it is larger than the sum of its proper divisors (281846723).

20011112221 is an equidigital number, since it uses as much as digits as its factorization.

20011112221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 281846722.

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

Adding to 20011112221 its reverse (12221111002), we get a palindrome (32232223223).

The spelling of 20011112221 in words is "twenty billion, eleven million, one hundred twelve thousand, two hundred twenty-one".