64392640 has 112 divisors (see below), whose sum is σ = 172565568. Its totient is φ = 22708224.

The previous prime is 64392631. The next prime is 64392649. The reversal of 64392640 is 4629346.

64392640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (64392631) and next prime (64392649).

It is a junction number, because it is equal to n+sod(n) for n = 64392596 and 64392605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64392649) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 95344 + ... + 96016.

It is an arithmetic number, because the mean of its divisors is an integer number (1540764).

Almost surely, 2^64392640 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 64392640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86282784).

64392640 is an abundant number, since it is smaller than the sum of its proper divisors (108172928).

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

64392640 is a wasteful number, since it uses less digits than its factorization.

64392640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 726 (or 716 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 34.

The square root of 64392640 is about 8024.5024767894. The cubic root of 64392640 is about 400.8163328683.

The spelling of 64392640 in words is "sixty-four million, three hundred ninety-two thousand, six hundred forty".