21276323 has 4 divisors (see below), whose sum is σ = 21962688. Its totient is φ = 20589960.

The previous prime is 21276317. The next prime is 21276329. The reversal of 21276323 is 32367212.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (21276317) and next prime (21276329).

It is a cyclic number.

It is not a de Polignac number, because 21276323 - 2¹⁸ = 21014179 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21276292 and 21276301.

It is not an unprimeable number, because it can be changed into a prime (21276329) 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 3 ways as a sum of consecutive naturals, for example, 343136 + ... + 343197.

It is an arithmetic number, because the mean of its divisors is an integer number (5490672).

Almost surely, 2^21276323 is an apocalyptic number.

21276323 is a deficient number, since it is larger than the sum of its proper divisors (686365).

21276323 is an equidigital number, since it uses as much as digits as its factorization.

21276323 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 686364.

The product of its digits is 3024, while the sum is 26.

The square root of 21276323 is about 4612.6264752308. The cubic root of 21276323 is about 277.0972346064.

The spelling of 21276323 in words is "twenty-one million, two hundred seventy-six thousand, three hundred twenty-three".