64638800 has 60 divisors (see below), whose sum is σ = 158276700. Its totient is φ = 25359360.

The previous prime is 64638797. The next prime is 64638803. The reversal of 64638800 is 883646.

It is an interprime number because it is at equal distance from previous prime (64638797) and next prime (64638803).

It can be written as a sum of positive squares in 6 ways, for example, as 4048144 + 60590656 = 2012^2 + 7784^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64638803) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 19676 + ... + 22724.

It is an arithmetic number, because the mean of its divisors is an integer number (2637945).

Almost surely, 2^64638800 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 64638800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (79138350).

64638800 is an abundant number, since it is smaller than the sum of its proper divisors (93637900).

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

64638800 is a wasteful number, since it uses less digits than its factorization.

64638800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3120 (or 3109 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 35.

The square root of 64638800 is about 8039.8258687611. The cubic root of 64638800 is about 401.3264299305.

The spelling of 64638800 in words is "sixty-four million, six hundred thirty-eight thousand, eight hundred".