21203021223 has 6 divisors (see below), whose sum is σ = 30626586224. Its totient is φ = 14135347476.

The previous prime is 21203021207. The next prime is 21203021267. The reversal of 21203021223 is 32212030212.

It is not a de Polignac number, because 21203021223 - 2⁴ = 21203021207 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21203021196 and 21203021205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21203011223) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1177945615 + ... + 1177945632.

Almost surely, 2^21203021223 is an apocalyptic number.

21203021223 is a deficient number, since it is larger than the sum of its proper divisors (9423565001).

21203021223 is a wasteful number, since it uses less digits than its factorization.

21203021223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2355891253 (or 2355891250 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

Adding to 21203021223 its reverse (32212030212), we get a palindrome (53415051435).

The spelling of 21203021223 in words is "twenty-one billion, two hundred three million, twenty-one thousand, two hundred twenty-three".