21131003 has 8 divisors (see below), whose sum is σ = 21481200. Its totient is φ = 20783488.

The previous prime is 21130987. The next prime is 21131009. The reversal of 21131003 is 30013112.

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 21131003 - 2⁴ = 21130987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21131009) 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, 20228 + ... + 21246.

It is an arithmetic number, because the mean of its divisors is an integer number (2685150).

Almost surely, 2^21131003 is an apocalyptic number.

21131003 is a deficient number, since it is larger than the sum of its proper divisors (350197).

21131003 is a wasteful number, since it uses less digits than its factorization.

21131003 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1341.

The product of its (nonzero) digits is 18, while the sum is 11.

The square root of 21131003 is about 4596.8470716351. The cubic root of 21131003 is about 276.4649230050.

Adding to 21131003 its reverse (30013112), we get a palindrome (51144115).

The spelling of 21131003 in words is "twenty-one million, one hundred thirty-one thousand, three".