21416817 has 8 divisors (see below), whose sum is σ = 28588896. Its totient is φ = 14261312.

The previous prime is 21416807. The next prime is 21416827. The reversal of 21416817 is 71861412.

It is an interprime number because it is at equal distance from previous prime (21416807) and next prime (21416827).

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 21416817 - 2⁸ = 21416561 is a prime.

It is a super-2 number, since 2×21416817² = 917360100822978, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21416807) 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 7 ways as a sum of consecutive naturals, for example, 723 + ... + 6584.

It is an arithmetic number, because the mean of its divisors is an integer number (3573612).

Almost surely, 2^21416817 is an apocalyptic number.

It is an amenable number.

21416817 is a deficient number, since it is larger than the sum of its proper divisors (7172079).

21416817 is an equidigital number, since it uses as much as digits as its factorization.

21416817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8287.

The product of its digits is 2688, while the sum is 30.

The square root of 21416817 is about 4627.8307013114. The cubic root of 21416817 is about 277.7058159842.

It can be divided in two parts, 214168 and 17, that added together give a triangular number (214185 = T₆₅₄).

The spelling of 21416817 in words is "twenty-one million, four hundred sixteen thousand, eight hundred seventeen".