21211231223 has 32 divisors (see below), whose sum is σ = 26783447040. Its totient is φ = 16348343040.

The previous prime is 21211231199. The next prime is 21211231231. The reversal of 21211231223 is 32213211212.

It is a cyclic number.

It is not a de Polignac number, because 21211231223 - 2¹⁴ = 21211214839 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21211231195 and 21211231204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211231253) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2678636 + ... + 2686542.

It is an arithmetic number, because the mean of its divisors is an integer number (836982720).

Almost surely, 2^21211231223 is an apocalyptic number.

21211231223 is a deficient number, since it is larger than the sum of its proper divisors (5572215817).

21211231223 is a wasteful number, since it uses less digits than its factorization.

21211231223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8687.

The product of its digits is 288, while the sum is 20.

Adding to 21211231223 its reverse (32213211212), we get a palindrome (53424442435).

The spelling of 21211231223 in words is "twenty-one billion, two hundred eleven million, two hundred thirty-one thousand, two hundred twenty-three".