19613664 has 240 divisors, whose sum is σ = 70253568. Its totient is φ = 5246208.

The previous prime is 19613653. The next prime is 19613689. The reversal of 19613664 is 46631691.

It is a Harshad number since it is a multiple of its sum of digits (36).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 417289 + ... + 417335.

Almost surely, 2^19613664 is an apocalyptic number.

19613664 is a gapful number since it is divisible by the number (14) 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 19613664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35126784).

19613664 is an abundant number, since it is smaller than the sum of its proper divisors (50639904).

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

19613664 is a wasteful number, since it uses less digits than its factorization.

19613664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99 (or 82 counting only the distinct ones).

The product of its digits is 23328, while the sum is 36.

The square root of 19613664 is about 4428.7316468714. The cubic root of 19613664 is about 269.6825899643.

It can be divided in two parts, 1961 and 3664, that added together give a square (5625 = 75²).

The spelling of 19613664 in words is "nineteen million, six hundred thirteen thousand, six hundred sixty-four".