64577920 has 64 divisors (see below), whose sum is σ = 168434640. Its totient is φ = 23480320.

The previous prime is 64577899. The next prime is 64577927. The reversal of 64577920 is 2977546.

It is a tau number, because it is divible by the number of its divisors (64).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64577927) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 2454 + ... + 11626.

Almost surely, 2^64577920 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 64577920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (84217320).

64577920 is an abundant number, since it is smaller than the sum of its proper divisors (103856720).

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

64577920 is a wasteful number, since it uses less digits than its factorization.

64577920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9203 (or 9191 counting only the distinct ones).

The product of its (nonzero) digits is 105840, while the sum is 40.

The square root of 64577920 is about 8036.0388251924. The cubic root of 64577920 is about 401.2003940319.

The spelling of 64577920 in words is "sixty-four million, five hundred seventy-seven thousand, nine hundred twenty".