19819680 has 96 divisors (see below), whose sum is σ = 63068544. Its totient is φ = 5231616.

The previous prime is 19819663. The next prime is 19819699. The reversal of 19819680 is 8691891.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 75229 + ... + 75491.

It is an arithmetic number, because the mean of its divisors is an integer number (656964).

Almost surely, 2^19819680 is an apocalyptic number.

19819680 is a gapful number since it is divisible by the number (10) 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 19819680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31534272).

19819680 is an abundant number, since it is smaller than the sum of its proper divisors (43248864).

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

19819680 is a wasteful number, since it uses less digits than its factorization.

19819680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 438 (or 430 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 42.

The square root of 19819680 is about 4451.9299185859. The cubic root of 19819680 is about 270.6235246610.

The spelling of 19819680 in words is "nineteen million, eight hundred nineteen thousand, six hundred eighty".