64521000 has 192 divisors, whose sum is σ = 223404480. Its totient is φ = 16790400.

The previous prime is 64520999. The next prime is 64521029. The reversal of 64521000 is 12546.

It is a happy number.

64521000 is a `hidden beast` number, since 645 + 21 + 0 + 0 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

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 47 ways as a sum of consecutive naturals, for example, 602947 + ... + 603053.

It is an arithmetic number, because the mean of its divisors is an integer number (1163565).

Almost surely, 2^64521000 is an apocalyptic number.

64521000 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 64521000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (111702240).

64521000 is an abundant number, since it is smaller than the sum of its proper divisors (158883480).

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

64521000 is a wasteful number, since it uses less digits than its factorization.

64521000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 201 (or 184 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 64521000 is about 8032.4964985987. The cubic root of 64521000 is about 401.0824845919.

Adding to 64521000 its reverse (12546), we get a palindrome (64533546).

The spelling of 64521000 in words is "sixty-four million, five hundred twenty-one thousand".