20001221223 has 4 divisors (see below), whose sum is σ = 26668294968. Its totient is φ = 13334147480.

The previous prime is 20001221171. The next prime is 20001221231. The reversal of 20001221223 is 32212210002.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20001221223 - 2¹² = 20001217127 is a prime.

It is a super-2 number, since 2×20001221223² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20001201223) 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, 3333536868 + ... + 3333536873.

It is an arithmetic number, because the mean of its divisors is an integer number (6667073742).

Almost surely, 2^20001221223 is an apocalyptic number.

20001221223 is a deficient number, since it is larger than the sum of its proper divisors (6667073745).

20001221223 is an equidigital number, since it uses as much as digits as its factorization.

20001221223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6667073744.

The product of its (nonzero) digits is 96, while the sum is 15.

Adding to 20001221223 its reverse (32212210002), we get a palindrome (52213431225).

The spelling of 20001221223 in words is "twenty billion, one million, two hundred twenty-one thousand, two hundred twenty-three".