20012112221 has 4 divisors (see below), whose sum is σ = 20012453472. Its totient is φ = 20011770972.

The previous prime is 20012112209. The next prime is 20012112223. The reversal of 20012112221 is 12221121002.

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 a de Polignac number, because none of the positive numbers 2^k-20012112221 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20012112196 and 20012112205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20012112223) 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, 57785 + ... + 208238.

It is an arithmetic number, because the mean of its divisors is an integer number (5003113368).

Almost surely, 2^20012112221 is an apocalyptic number.

It is an amenable number.

20012112221 is a deficient number, since it is larger than the sum of its proper divisors (341251).

20012112221 is an equidigital number, since it uses as much as digits as its factorization.

20012112221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 341250.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 20012112221 its reverse (12221121002), we get a palindrome (32233233223).

The spelling of 20012112221 in words is "twenty billion, twelve million, one hundred twelve thousand, two hundred twenty-one".