21079273 has 4 divisors (see below), whose sum is σ = 21102480. Its totient is φ = 21056068.

The previous prime is 21079271. The next prime is 21079297. The reversal of 21079273 is 37297012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21079273 - 2¹ = 21079271 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21079271) 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, 10183 + ... + 12076.

It is an arithmetic number, because the mean of its divisors is an integer number (5275620).

Almost surely, 2^21079273 is an apocalyptic number.

It is an amenable number.

21079273 is a deficient number, since it is larger than the sum of its proper divisors (23207).

21079273 is an equidigital number, since it uses as much as digits as its factorization.

21079273 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23206.

The product of its (nonzero) digits is 5292, while the sum is 31.

The square root of 21079273 is about 4591.2169410735. The cubic root of 21079273 is about 276.2391375922.

The spelling of 21079273 in words is "twenty-one million, seventy-nine thousand, two hundred seventy-three".