21448418 has 8 divisors (see below), whose sum is σ = 32192748. Its totient is φ = 10717504.

The previous prime is 21448379. The next prime is 21448433. The reversal of 21448418 is 81484412.

It can be written as a sum of positive squares in 2 ways, for example, as 18037009 + 3411409 = 4247^2 + 1847^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon 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, 3230 + ... + 7302.

Almost surely, 2^21448418 is an apocalyptic number.

21448418 is a deficient number, since it is larger than the sum of its proper divisors (10744330).

21448418 is a wasteful number, since it uses less digits than its factorization.

21448418 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6708.

The product of its digits is 8192, while the sum is 32.

The square root of 21448418 is about 4631.2436774586. The cubic root of 21448418 is about 277.8423359401.

The spelling of 21448418 in words is "twenty-one million, four hundred forty-eight thousand, four hundred eighteen".