21273417 has 12 divisors (see below), whose sum is σ = 33521904. Its totient is φ = 12892920.

The previous prime is 21273391. The next prime is 21273431. The reversal of 21273417 is 71437212.

It is a happy number.

It is not a de Polignac number, because 21273417 - 2⁷ = 21273289 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21273437) 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 11 ways as a sum of consecutive naturals, for example, 107343 + ... + 107540.

It is an arithmetic number, because the mean of its divisors is an integer number (2793492).

Almost surely, 2^21273417 is an apocalyptic number.

It is an amenable number.

21273417 is a deficient number, since it is larger than the sum of its proper divisors (12248487).

21273417 is a wasteful number, since it uses less digits than its factorization.

21273417 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214900 (or 214897 counting only the distinct ones).

The product of its digits is 2352, while the sum is 27.

The square root of 21273417 is about 4612.3114595612. The cubic root of 21273417 is about 277.0846183721.

The spelling of 21273417 in words is "twenty-one million, two hundred seventy-three thousand, four hundred seventeen".