19640064 has 72 divisors (see below), whose sum is σ = 52980480. Its totient is φ = 6458368.

The previous prime is 19640063. The next prime is 19640069. The reversal of 19640064 is 46004691.

It is a super-2 number, since 2×19640064² = 771464227848192, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19640063) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 82057 + ... + 82295.

It is an arithmetic number, because the mean of its divisors is an integer number (735840).

Almost surely, 2^19640064 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 19640064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26490240).

19640064 is an abundant number, since it is smaller than the sum of its proper divisors (33340416).

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

19640064 is a wasteful number, since it uses less digits than its factorization.

19640064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 365 (or 351 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 30.

The square root of 19640064 is about 4431.7111819251. The cubic root of 19640064 is about 269.8035333437.

The spelling of 19640064 in words is "nineteen million, six hundred forty thousand, sixty-four".