64655680 has 28 divisors (see below), whose sum is σ = 153962100. Its totient is φ = 25862144.

The previous prime is 64655671. The next prime is 64655693. The reversal of 64655680 is 8655646.

It can be written as a sum of positive squares in 2 ways, for example, as 18524416 + 46131264 = 4304^2 + 6792^2 .

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 100705 + ... + 101344.

Almost surely, 2^64655680 is an apocalyptic number.

It is an amenable number.

64655680 is an abundant number, since it is smaller than the sum of its proper divisors (89306420).

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

64655680 is a wasteful number, since it uses less digits than its factorization.

64655680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 202066 (or 202056 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 40.

The square root of 64655680 is about 8040.8755742145. The cubic root of 64655680 is about 401.3613614810.

The spelling of 64655680 in words is "sixty-four million, six hundred fifty-five thousand, six hundred eighty".