21822478 has 16 divisors (see below), whose sum is σ = 33297264. Its totient is φ = 10725120.

The previous prime is 21822473. The next prime is 21822487. The reversal of 21822478 is 87422812.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21822473) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 37933 + ... + 38503.

It is an arithmetic number, because the mean of its divisors is an integer number (2081079).

Almost surely, 2^21822478 is an apocalyptic number.

21822478 is a deficient number, since it is larger than the sum of its proper divisors (11474786).

21822478 is a wasteful number, since it uses less digits than its factorization.

21822478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 867.

The product of its digits is 14336, while the sum is 34.

The square root of 21822478 is about 4671.4535211217. The cubic root of 21822478 is about 279.4482245955.

The spelling of 21822478 in words is "twenty-one million, eight hundred twenty-two thousand, four hundred seventy-eight".