21000001003 has 8 divisors (see below), whose sum is σ = 21144850272. Its totient is φ = 20855379456.

The previous prime is 21000000979. The next prime is 21000001013. The reversal of 21000001003 is 30010000012.

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 21000001003 - 2³³ = 12410066411 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21000001013) 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, 130251 + ... + 242827.

It is an arithmetic number, because the mean of its divisors is an integer number (2643106284).

Almost surely, 2^21000001003 is an apocalyptic number.

21000001003 is a deficient number, since it is larger than the sum of its proper divisors (144849269).

21000001003 is a wasteful number, since it uses less digits than its factorization.

21000001003 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113861.

The product of its (nonzero) digits is 6, while the sum is 7.

Adding to 21000001003 its reverse (30010000012), we get a palindrome (51010001015).

Subtracting 21000001003 from its reverse (30010000012), we obtain a palindrome (9009999009).

The spelling of 21000001003 in words is "twenty-one billion, one thousand, three".