21102030321 has 8 divisors (see below), whose sum is σ = 28304520384. Its totient is φ = 13983780240.

The previous prime is 21102030319. The next prime is 21102030337. The reversal of 21102030321 is 12303020112.

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

It is not a de Polignac number, because 21102030321 - 2¹ = 21102030319 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21102030321.

It is not an unprimeable number, because it can be changed into a prime (21102030361) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21059410 + ... + 21060411.

It is an arithmetic number, because the mean of its divisors is an integer number (3538065048).

Almost surely, 2^21102030321 is an apocalyptic number.

It is an amenable number.

21102030321 is a deficient number, since it is larger than the sum of its proper divisors (7202490063).

21102030321 is a wasteful number, since it uses less digits than its factorization.

21102030321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42119991.

The product of its (nonzero) digits is 72, while the sum is 15.

Adding to 21102030321 its reverse (12303020112), we get a palindrome (33405050433).

The spelling of 21102030321 in words is "twenty-one billion, one hundred two million, thirty thousand, three hundred twenty-one".