21774459 has 16 divisors (see below), whose sum is σ = 33286400. Its totient is φ = 12402720.

The previous prime is 21774451. The next prime is 21774479. The reversal of 21774459 is 95447712.

It is not a de Polignac number, because 21774459 - 2³ = 21774451 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21774451) 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 15 ways as a sum of consecutive naturals, for example, 5844 + ... + 8814.

It is an arithmetic number, because the mean of its divisors is an integer number (2080400).

Almost surely, 2^21774459 is an apocalyptic number.

21774459 is a deficient number, since it is larger than the sum of its proper divisors (11511941).

21774459 is a wasteful number, since it uses less digits than its factorization.

21774459 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3330.

The product of its digits is 70560, while the sum is 39.

The square root of 21774459 is about 4666.3110697852. The cubic root of 21774459 is about 279.2431046152.

The spelling of 21774459 in words is "twenty-one million, seven hundred seventy-four thousand, four hundred fifty-nine".