21111120321 has 8 divisors (see below), whose sum is σ = 28180259904. Its totient is φ = 14058030480.

The previous prime is 21111120307. The next prime is 21111120361. The reversal of 21111120321 is 12302111112.

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

It is not a de Polignac number, because 21111120321 - 2¹⁹ = 21110596033 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21111120321.

It is not an unprimeable number, because it can be changed into a prime (21111120361) 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, 4009365 + ... + 4014626.

It is an arithmetic number, because the mean of its divisors is an integer number (3522532488).

Almost surely, 2^21111120321 is an apocalyptic number.

It is an amenable number.

21111120321 is a deficient number, since it is larger than the sum of its proper divisors (7069139583).

21111120321 is an equidigital number, since it uses as much as digits as its factorization.

21111120321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8024871.

The product of its (nonzero) digits is 24, while the sum is 15.

Adding to 21111120321 its reverse (12302111112), we get a palindrome (33413231433).

The spelling of 21111120321 in words is "twenty-one billion, one hundred eleven million, one hundred twenty thousand, three hundred twenty-one".