19397664 has 192 divisors, whose sum is σ = 66890880. Its totient is φ = 5391360.

The previous prime is 19397617. The next prime is 19397683. The reversal of 19397664 is 46679391.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 123474 + ... + 123630.

It is an arithmetic number, because the mean of its divisors is an integer number (348390).

Almost surely, 2^19397664 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19397664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33445440).

19397664 is an abundant number, since it is smaller than the sum of its proper divisors (47493216).

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

19397664 is a wasteful number, since it uses less digits than its factorization.

19397664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 200 (or 186 counting only the distinct ones).

The product of its digits is 244944, while the sum is 45.

The square root of 19397664 is about 4404.2779203860. The cubic root of 19397664 is about 268.6889528548.

The spelling of 19397664 in words is "nineteen million, three hundred ninety-seven thousand, six hundred sixty-four".