19640320 has 104 divisors (see below), whose sum is σ = 54257184. Its totient is φ = 6684672.

The previous prime is 19640311. The next prime is 19640323. The reversal of 19640320 is 2304691.

It is a hoax number, since the sum of its digits (25) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (19640323) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 143292 + ... + 143428.

Almost surely, 2^19640320 is an apocalyptic number.

19640320 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 19640320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27128592).

19640320 is an abundant number, since it is smaller than the sum of its proper divisors (34616864).

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

19640320 is an equidigital number, since it uses as much as digits as its factorization.

19640320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173 (or 151 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 19640320 is about 4431.7400645796. The cubic root of 19640320 is about 269.8047055973.

The spelling of 19640320 in words is "nineteen million, six hundred forty thousand, three hundred twenty".