21809348 has 12 divisors (see below), whose sum is σ = 41636112. Its totient is φ = 9913320.

The previous prime is 21809327. The next prime is 21809353. The reversal of 21809348 is 84390812.

It is a happy 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, 247790 + ... + 247877.

It is an arithmetic number, because the mean of its divisors is an integer number (3469676).

Almost surely, 2^21809348 is an apocalyptic number.

It is an amenable number.

21809348 is a deficient number, since it is larger than the sum of its proper divisors (19826764).

21809348 is a wasteful number, since it uses less digits than its factorization.

21809348 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 495682 (or 495680 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 35.

The square root of 21809348 is about 4670.0479654924. The cubic root of 21809348 is about 279.3921678496.

The spelling of 21809348 in words is "twenty-one million, eight hundred nine thousand, three hundred forty-eight".