19816488 has 80 divisors (see below), whose sum is σ = 56649780. Its totient is φ = 6469632.

The previous prime is 19816481. The next prime is 19816513. The reversal of 19816488 is 88461891.

It can be written as a sum of positive squares in 2 ways, for example, as 15824484 + 3992004 = 3978^2 + 1998^2 .

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (19816481) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 34056 + ... + 34632.

Almost surely, 2^19816488 is an apocalyptic number.

19816488 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19816488, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28324890).

19816488 is an abundant number, since it is smaller than the sum of its proper divisors (36833292).

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

19816488 is a wasteful number, since it uses less digits than its factorization.

19816488 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 648 (or 635 counting only the distinct ones).

The product of its digits is 110592, while the sum is 45.

The square root of 19816488 is about 4451.5714079412. The cubic root of 19816488 is about 270.6089957236.

The spelling of 19816488 in words is "nineteen million, eight hundred sixteen thousand, four hundred eighty-eight".