64648640 has 224 divisors, whose sum is σ = 195072000. Its totient is φ = 20321280.

The previous prime is 64648613. The next prime is 64648667. The reversal of 64648640 is 4684646.

It is an interprime number because it is at equal distance from previous prime (64648613) and next prime (64648667).

It is a tau number, because it is divible by the number of its divisors (224).

It is a Harshad number since it is a multiple of its sum of digits (38).

It is a junction number, because it is equal to n+sod(n) for n = 64648594 and 64648603.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2085425 + ... + 2085455.

Almost surely, 2^64648640 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 64648640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (97536000).

64648640 is an abundant number, since it is smaller than the sum of its proper divisors (130423360).

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

64648640 is a wasteful number, since it uses less digits than its factorization.

64648640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88 (or 64 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 38.

The square root of 64648640 is about 8040.4377990256. The cubic root of 64648640 is about 401.3467936114.

The spelling of 64648640 in words is "sixty-four million, six hundred forty-eight thousand, six hundred forty".