64323640 has 64 divisors (see below), whose sum is σ = 152409600. Its totient is φ = 24385152.

The previous prime is 64323601. The next prime is 64323641. The reversal of 64323640 is 4632346.

It is a junction number, because it is equal to n+sod(n) for n = 64323599 and 64323608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64323641) 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 15 ways as a sum of consecutive naturals, for example, 127629 + ... + 128131.

It is an arithmetic number, because the mean of its divisors is an integer number (2381400).

Almost surely, 2^64323640 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 64323640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (76204800).

64323640 is an abundant number, since it is smaller than the sum of its proper divisors (88085960).

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

64323640 is a wasteful number, since it uses less digits than its factorization.

64323640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 676 (or 672 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 28.

The square root of 64323640 is about 8020.2019924688. The cubic root of 64323640 is about 400.6731166496.

Adding to 64323640 its reverse (4632346), we get a palindrome (68955986).

The spelling of 64323640 in words is "sixty-four million, three hundred twenty-three thousand, six hundred forty".