21667413 has 16 divisors (see below), whose sum is σ = 29350080. Its totient is φ = 14217216.

The previous prime is 21667397. The next prime is 21667417. The reversal of 21667413 is 31476612.

It is not a de Polignac number, because 21667413 - 2⁴ = 21667397 is a prime.

It is a super-2 number, since 2×21667413² = 938953572225138, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21667417) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 84181 + ... + 84437.

It is an arithmetic number, because the mean of its divisors is an integer number (1834380).

Almost surely, 2^21667413 is an apocalyptic number.

It is an amenable number.

21667413 is a deficient number, since it is larger than the sum of its proper divisors (7682667).

21667413 is a wasteful number, since it uses less digits than its factorization.

21667413 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 596.

The product of its digits is 6048, while the sum is 30.

The square root of 21667413 is about 4654.8268496261. The cubic root of 21667413 is about 278.7847545263.

The spelling of 21667413 in words is "twenty-one million, six hundred sixty-seven thousand, four hundred thirteen".