21130503 has 8 divisors (see below), whose sum is σ = 28267008. Its totient is φ = 14040504.

The previous prime is 21130481. The next prime is 21130511. The reversal of 21130503 is 30503112.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21130503 - 2⁸ = 21130247 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21130573) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10551 + ... + 12392.

It is an arithmetic number, because the mean of its divisors is an integer number (3533376).

Almost surely, 2^21130503 is an apocalyptic number.

21130503 is a deficient number, since it is larger than the sum of its proper divisors (7136505).

21130503 is a wasteful number, since it uses less digits than its factorization.

21130503 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23253.

The product of its (nonzero) digits is 90, while the sum is 15.

The square root of 21130503 is about 4596.7926862107. The cubic root of 21130503 is about 276.4627424246.

Adding to 21130503 its reverse (30503112), we get a palindrome (51633615).

The spelling of 21130503 in words is "twenty-one million, one hundred thirty thousand, five hundred three".