21130005 has 16 divisors (see below), whose sum is σ = 36408960. Its totient is φ = 10402368.

The previous prime is 21130001. The next prime is 21130027. The reversal of 21130005 is 50003112.

It is not a de Polignac number, because 21130005 - 2² = 21130001 is a prime.

It is a super-2 number, since 2×21130005² = 892954222600050, which contains 22 as substring.

It is a congruent number.

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 15 ways as a sum of consecutive naturals, for example, 53985 + ... + 54374.

It is an arithmetic number, because the mean of its divisors is an integer number (2275560).

Almost surely, 2^21130005 is an apocalyptic number.

It is an amenable number.

21130005 is a deficient number, since it is larger than the sum of its proper divisors (15278955).

21130005 is a wasteful number, since it uses less digits than its factorization.

21130005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108380.

The product of its (nonzero) digits is 30, while the sum is 12.

The square root of 21130005 is about 4596.7385176884. The cubic root of 21130005 is about 276.4605705324.

Adding to 21130005 its reverse (50003112), we get a palindrome (71133117).

The spelling of 21130005 in words is "twenty-one million, one hundred thirty thousand, five".