21003203513 has 16 divisors (see below), whose sum is σ = 22462632960. Its totient is φ = 19600056000.

The previous prime is 21003203509. The next prime is 21003203531. The reversal of 21003203513 is 31530230012.

It is not a de Polignac number, because 21003203513 - 2² = 21003203509 is a prime.

It is a super-2 number, since 2×21003203513² (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 (21003203563) 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, 97208 + ... + 226838.

It is an arithmetic number, because the mean of its divisors is an integer number (1403914560).

Almost surely, 2^21003203513 is an apocalyptic number.

It is an amenable number.

21003203513 is a deficient number, since it is larger than the sum of its proper divisors (1459429447).

21003203513 is a wasteful number, since it uses less digits than its factorization.

21003203513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129848.

The product of its (nonzero) digits is 540, while the sum is 20.

Adding to 21003203513 its reverse (31530230012), we get a palindrome (52533433525).

The spelling of 21003203513 in words is "twenty-one billion, three million, two hundred three thousand, five hundred thirteen".