64315640 has 32 divisors (see below), whose sum is σ = 144970560. Its totient is φ = 25680000.

The previous prime is 64315637. The next prime is 64315651. The reversal of 64315640 is 4651346.

It is a happy number.

It is a super-3 number, since 3×64315640³ (a number of 24 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28970 + ... + 31110.

It is an arithmetic number, because the mean of its divisors is an integer number (4530330).

Almost surely, 2^64315640 is an apocalyptic number.

It is an amenable number.

64315640 is an abundant number, since it is smaller than the sum of its proper divisors (80654920).

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

64315640 is a wasteful number, since it uses less digits than its factorization.

64315640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2903 (or 2899 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 29.

The square root of 64315640 is about 8019.7032364047. The cubic root of 64315640 is about 400.6565052460.

Adding to 64315640 its reverse (4651346), we get a palindrome (68966986).

The spelling of 64315640 in words is "sixty-four million, three hundred fifteen thousand, six hundred forty".