21419273 has 4 divisors (see below), whose sum is σ = 21430788. Its totient is φ = 21407760.

The previous prime is 21419267. The next prime is 21419287. The reversal of 21419273 is 37291412.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 10582009 + 10837264 = 3253^2 + 3292^2 .

It is a cyclic number.

It is not a de Polignac number, because 21419273 - 2¹⁶ = 21353737 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21419173) 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, 2258 + ... + 6923.

It is an arithmetic number, because the mean of its divisors is an integer number (5357697).

Almost surely, 2^21419273 is an apocalyptic number.

It is an amenable number.

21419273 is a deficient number, since it is larger than the sum of its proper divisors (11515).

21419273 is an equidigital number, since it uses as much as digits as its factorization.

21419273 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11514.

The product of its digits is 3024, while the sum is 29.

The square root of 21419273 is about 4628.0960448115. The cubic root of 21419273 is about 277.7164309978.

The spelling of 21419273 in words is "twenty-one million, four hundred nineteen thousand, two hundred seventy-three".