21021123003 has 4 divisors (see below), whose sum is σ = 28028164008. Its totient is φ = 14014082000.

The previous prime is 21021122959. The next prime is 21021123007. The reversal of 21021123003 is 30032112012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21021123003 - 2¹⁷ = 21020991931 is a prime.

It is a super-2 number, since 2×21021123003² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21021123007) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3503520498 + ... + 3503520503.

It is an arithmetic number, because the mean of its divisors is an integer number (7007041002).

Almost surely, 2^21021123003 is an apocalyptic number.

21021123003 is a deficient number, since it is larger than the sum of its proper divisors (7007041005).

21021123003 is an equidigital number, since it uses as much as digits as its factorization.

21021123003 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7007041004.

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

Adding to 21021123003 its reverse (30032112012), we get a palindrome (51053235015).

The spelling of 21021123003 in words is "twenty-one billion, twenty-one million, one hundred twenty-three thousand, three".