19696640 has 44 divisors (see below), whose sum is σ = 47261136. Its totient is φ = 7876608.

The previous prime is 19696637. The next prime is 19696643. The reversal of 19696640 is 4669691.

It is an interprime number because it is at equal distance from previous prime (19696637) and next prime (19696643).

It is not an unprimeable number, because it can be changed into a prime (19696643) by changing a digit.

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, 3197 + ... + 7043.

Almost surely, 2^19696640 is an apocalyptic number.

19696640 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 19696640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23630568).

19696640 is an abundant number, since it is smaller than the sum of its proper divisors (27564496).

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

19696640 is an equidigital number, since it uses as much as digits as its factorization.

19696640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3872 (or 3854 counting only the distinct ones).

The product of its (nonzero) digits is 69984, while the sum is 41.

The square root of 19696640 is about 4438.0896791300. The cubic root of 19696640 is about 270.0623541401.

The spelling of 19696640 in words is "nineteen million, six hundred ninety-six thousand, six hundred forty".