21000203003 has 16 divisors (see below), whose sum is σ = 24338504736. Its totient is φ = 17945418240.

The previous prime is 21000202991. The next prime is 21000203009. The reversal of 21000203003 is 30030200012.

It is a cyclic number.

It is not a de Polignac number, because 21000203003 - 2¹⁰ = 21000201979 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21000203009) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 765401 + ... + 792362.

It is an arithmetic number, because the mean of its divisors is an integer number (1521156546).

Almost surely, 2^21000203003 is an apocalyptic number.

21000203003 is a deficient number, since it is larger than the sum of its proper divisors (3338301733).

21000203003 is a wasteful number, since it uses less digits than its factorization.

21000203003 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1557854.

The product of its (nonzero) digits is 36, while the sum is 11.

Adding to 21000203003 its reverse (30030200012), we get a palindrome (51030403015).

The spelling of 21000203003 in words is "twenty-one billion, two hundred three thousand, three".