64995840 has 480 divisors, whose sum is σ = 285981696. Its totient is φ = 13271040.

The previous prime is 64995817. The next prime is 64995851. The reversal of 64995840 is 4859946.

It is a happy number.

64995840 is a `hidden beast` number, since 64 + 9 + 9 + 584 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (480).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2096625 + ... + 2096655.

Almost surely, 2^64995840 is an apocalyptic number.

64995840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 64995840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (142990848).

64995840 is an abundant number, since it is smaller than the sum of its proper divisors (220985856).

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

64995840 is a wasteful number, since it uses less digits than its factorization.

64995840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80 (or 61 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The square root of 64995840 is about 8061.9997519226. Note that the first 3 decimals coincide. The cubic root of 64995840 is about 402.0639981276.

The spelling of 64995840 in words is "sixty-four million, nine hundred ninety-five thousand, eight hundred forty".