21130009 has 8 divisors (see below), whose sum is σ = 21994560. Its totient is φ = 20274576.

The previous prime is 21130001. The next prime is 21130027. The reversal of 21130009 is 90003112.

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 21130009 - 2³ = 21130001 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21129974 and 21130001.

It is not an unprimeable number, because it can be changed into a prime (21130001) 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, 2662 + ... + 7024.

It is an arithmetic number, because the mean of its divisors is an integer number (2749320).

Almost surely, 2^21130009 is an apocalyptic number.

21130009 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

21130009 is a deficient number, since it is larger than the sum of its proper divisors (864551).

21130009 is a wasteful number, since it uses less digits than its factorization.

21130009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4559.

The product of its (nonzero) digits is 54, while the sum is 16.

The square root of 21130009 is about 4596.7389527795. The cubic root of 21130009 is about 276.4605879774.

The spelling of 21130009 in words is "twenty-one million, one hundred thirty thousand, nine".