21003320123 has 8 divisors (see below), whose sum is σ = 22241252880. Its totient is φ = 19765658880.

The previous prime is 21003320027. The next prime is 21003320147. The reversal of 21003320123 is 32102330012.

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 21003320123 - 2⁸ = 21003319867 is a prime.

It is a super-2 number, since 2×21003320123² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21003323123) 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, 103823 + ... + 229751.

It is an arithmetic number, because the mean of its divisors is an integer number (2780156610).

Almost surely, 2^21003320123 is an apocalyptic number.

21003320123 is a deficient number, since it is larger than the sum of its proper divisors (1237932757).

21003320123 is a wasteful number, since it uses less digits than its factorization.

21003320123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135757.

The product of its (nonzero) digits is 216, while the sum is 17.

Adding to 21003320123 its reverse (32102330012), we get a palindrome (53105650135).

The spelling of 21003320123 in words is "twenty-one billion, three million, three hundred twenty thousand, one hundred twenty-three".