64319640 has 128 divisors (see below), whose sum is σ = 240606720. Its totient is φ = 13363200.

The previous prime is 64319639. The next prime is 64319669. The reversal of 64319640 is 4691346.

64319640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5760 + ... + 12720.

It is an arithmetic number, because the mean of its divisors is an integer number (1879740).

Almost surely, 2^64319640 is an apocalyptic number.

64319640 is a gapful number since it is divisible by the number (60) 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 64319640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (120303360).

64319640 is an abundant number, since it is smaller than the sum of its proper divisors (176287080).

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

64319640 is a wasteful number, since it uses less digits than its factorization.

64319640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6993 (or 6989 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 33.

The square root of 64319640 is about 8019.9526183139. The cubic root of 64319640 is about 400.6648111200.

The spelling of 64319640 in words is "sixty-four million, three hundred nineteen thousand, six hundred forty".