21031230321 has 24 divisors (see below), whose sum is σ = 32189119040. Its totient is φ = 13194900000.

The previous prime is 21031230307. The next prime is 21031230343. The reversal of 21031230321 is 12303213012.

21031230321 is a `hidden beast` number, since 2 + 1 + 0 + 312 + 30 + 321 = 666.

It is not a de Polignac number, because 21031230321 - 2¹⁴ = 21031213937 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21031230294 and 21031230303.

It is not an unprimeable number, because it can be changed into a prime (21031230301) 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 23 ways as a sum of consecutive naturals, for example, 381430 + ... + 433071.

Almost surely, 2^21031230321 is an apocalyptic number.

It is an amenable number.

21031230321 is a deficient number, since it is larger than the sum of its proper divisors (11157888719).

21031230321 is a wasteful number, since it uses less digits than its factorization.

21031230321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 814677 (or 814674 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

Adding to 21031230321 its reverse (12303213012), we get a palindrome (33334443333).

The spelling of 21031230321 in words is "twenty-one billion, thirty-one million, two hundred thirty thousand, three hundred twenty-one".