21040032321 has 48 divisors (see below), whose sum is σ = 38163041280. Its totient is φ = 10851204960.

The previous prime is 21040032313. The next prime is 21040032331. The reversal of 21040032321 is 12323004012.

21040032321 is a `hidden beast` number, since 210 + 400 + 32 + 3 + 21 = 666.

It is not a de Polignac number, because 21040032321 - 2³ = 21040032313 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21040032294 and 21040032303.

It is not an unprimeable number, because it can be changed into a prime (21040032331) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 12885 + ... + 205538.

It is an arithmetic number, because the mean of its divisors is an integer number (795063360).

Almost surely, 2^21040032321 is an apocalyptic number.

21040032321 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21040032321 is a deficient number, since it is larger than the sum of its proper divisors (17123008959).

21040032321 is a wasteful number, since it uses less digits than its factorization.

21040032321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 218586 (or 218583 counting only the distinct ones).

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

Adding to 21040032321 its reverse (12323004012), we get a palindrome (33363036333).

The spelling of 21040032321 in words is "twenty-one billion, forty million, thirty-two thousand, three hundred twenty-one".