19947808 has 24 divisors (see below), whose sum is σ = 40981248. Its totient is φ = 9539904.

The previous prime is 19947797. The next prime is 19947869. The reversal of 19947808 is 80874991.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (46).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12816 + ... + 14287.

It is an arithmetic number, because the mean of its divisors is an integer number (1707552).

Almost surely, 2^19947808 is an apocalyptic number.

It is an amenable number.

19947808 is an abundant number, since it is smaller than the sum of its proper divisors (21033440).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19947808 is a wasteful number, since it uses less digits than its factorization.

19947808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27136 (or 27128 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 46.

The square root of 19947808 is about 4466.2969001176. The cubic root of 19947808 is about 271.2054378295.

The spelling of 19947808 in words is "nineteen million, nine hundred forty-seven thousand, eight hundred eight".