21012023003 has 4 divisors (see below), whose sum is σ = 21012325728. Its totient is φ = 21011720280.

The previous prime is 21012022979. The next prime is 21012023017. The reversal of 21012023003 is 30032021012.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 21012023003 - 2¹⁶ = 21011957467 is a prime.

It is a super-2 number, since 2×21012023003² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21012023093) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10325 + ... + 205257.

It is an arithmetic number, because the mean of its divisors is an integer number (5253081432).

Almost surely, 2^21012023003 is an apocalyptic number.

21012023003 is a deficient number, since it is larger than the sum of its proper divisors (302725).

21012023003 is a wasteful number, since it uses less digits than its factorization.

21012023003 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 302724.

The product of its (nonzero) digits is 72, while the sum is 14.

Adding to 21012023003 its reverse (30032021012), we get a palindrome (51044044015).

The spelling of 21012023003 in words is "twenty-one billion, twelve million, twenty-three thousand, three".