21531430223 has 8 divisors (see below), whose sum is σ = 22906036080. Its totient is φ = 20168830080.

The previous prime is 21531430181. The next prime is 21531430229. The reversal of 21531430223 is 32203413512.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21531430223 - 2¹² = 21531426127 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21531430192 and 21531430201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21531430229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2997728 + ... + 3004901.

It is an arithmetic number, because the mean of its divisors is an integer number (2863254510).

Almost surely, 2^21531430223 is an apocalyptic number.

21531430223 is a deficient number, since it is larger than the sum of its proper divisors (1374605857).

21531430223 is a wasteful number, since it uses less digits than its factorization.

21531430223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6002857.

The product of its (nonzero) digits is 4320, while the sum is 26.

Adding to 21531430223 its reverse (32203413512), we get a palindrome (53734843735).

The spelling of 21531430223 in words is "twenty-one billion, five hundred thirty-one million, four hundred thirty thousand, two hundred twenty-three".