64605780 has 144 divisors (see below), whose sum is σ = 212756544. Its totient is φ = 15805440.

The previous prime is 64605773. The next prime is 64605799. The reversal of 64605780 is 8750646.

It is a happy number.

64605780 is a `hidden beast` number, since 646 + 0 + 5 + 7 + 8 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

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, 131335 + ... + 131825.

It is an arithmetic number, because the mean of its divisors is an integer number (1477476).

Almost surely, 2^64605780 is an apocalyptic number.

64605780 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 64605780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106378272).

64605780 is an abundant number, since it is smaller than the sum of its proper divisors (148150764).

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

64605780 is a wasteful number, since it uses less digits than its factorization.

64605780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 566 (or 561 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 36.

The square root of 64605780 is about 8037.7720793762. The cubic root of 64605780 is about 401.2580806012.

The spelling of 64605780 in words is "sixty-four million, six hundred five thousand, seven hundred eighty".