21448705 has 4 divisors (see below), whose sum is σ = 25738452. Its totient is φ = 17158960.

The previous prime is 21448667. The next prime is 21448711. The reversal of 21448705 is 50784412.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2238016 + 19210689 = 1496^2 + 4383^2 .

It is not a de Polignac number, because 21448705 - 2¹¹ = 21446657 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2144866 + ... + 2144875.

It is an arithmetic number, because the mean of its divisors is an integer number (6434613).

Almost surely, 2^21448705 is an apocalyptic number.

It is an amenable number.

21448705 is a deficient number, since it is larger than the sum of its proper divisors (4289747).

21448705 is an equidigital number, since it uses as much as digits as its factorization.

21448705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4289746.

The product of its (nonzero) digits is 8960, while the sum is 31.

The square root of 21448705 is about 4631.2746625524. The cubic root of 21448705 is about 277.8435751985.

The spelling of 21448705 in words is "twenty-one million, four hundred forty-eight thousand, seven hundred five".