64921824 has 252 divisors, whose sum is σ = 219797928. Its totient is φ = 18817920.

The previous prime is 64921811. The next prime is 64921859. The reversal of 64921824 is 42812946.

64921824 is a `hidden beast` number, since 649 + 2 + 1 + 8 + 2 + 4 = 666.

64921824 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 41 ways as a sum of consecutive naturals, for example, 2822677 + ... + 2822699.

It is an arithmetic number, because the mean of its divisors is an integer number (872214).

Almost surely, 2^64921824 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 64921824, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (109898964).

64921824 is an abundant number, since it is smaller than the sum of its proper divisors (154876104).

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

64921824 is a wasteful number, since it uses less digits than its factorization.

64921824 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73 (or 39 counting only the distinct ones).

The product of its digits is 27648, while the sum is 36.

The square root of 64921824 is about 8057.4080199528. The cubic root of 64921824 is about 401.9113192668.

The spelling of 64921824 in words is "sixty-four million, nine hundred twenty-one thousand, eight hundred twenty-four".