21001123003 has 24 divisors (see below), whose sum is σ = 25106955072. Its totient is φ = 17502718464.

The previous prime is 21001122979. The next prime is 21001123027. The reversal of 21001123003 is 30032110012.

It is an interprime number because it is at equal distance from previous prime (21001122979) and next prime (21001123027).

It is not a de Polignac number, because 21001123003 - 2¹³ = 21001114811 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21001120003) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3653950 + ... + 3659692.

It is an arithmetic number, because the mean of its divisors is an integer number (1046123128).

Almost surely, 2^21001123003 is an apocalyptic number.

21001123003 is a deficient number, since it is larger than the sum of its proper divisors (4105832069).

21001123003 is a wasteful number, since it uses less digits than its factorization.

21001123003 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7811 (or 7804 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 13.

Adding to 21001123003 its reverse (30032110012), we get a palindrome (51033233015).

The spelling of 21001123003 in words is "twenty-one billion, one million, one hundred twenty-three thousand, three".