21040020303 has 4 divisors (see below), whose sum is σ = 28053360408. Its totient is φ = 14026680200.

The previous prime is 21040020283. The next prime is 21040020311. The reversal of 21040020303 is 30302004012.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21040020303 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21040020373) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3506670048 + ... + 3506670053.

It is an arithmetic number, because the mean of its divisors is an integer number (7013340102).

Almost surely, 2^21040020303 is an apocalyptic number.

21040020303 is a deficient number, since it is larger than the sum of its proper divisors (7013340105).

21040020303 is an equidigital number, since it uses as much as digits as its factorization.

21040020303 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7013340104.

The product of its (nonzero) digits is 144, while the sum is 15.

Adding to 21040020303 its reverse (30302004012), we get a palindrome (51342024315).

The spelling of 21040020303 in words is "twenty-one billion, forty million, twenty thousand, three hundred three".