64604521 has 4 divisors (see below), whose sum is σ = 64729044. Its totient is φ = 64480000.

The previous prime is 64604497. The next prime is 64604537. The reversal of 64604521 is 12540646.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 17338896 + 47265625 = 4164^2 + 6875^2 .

It is a cyclic number.

It is not a de Polignac number, because 64604521 - 2²¹ = 62507369 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 64604521.

It is not an unprimeable number, because it can be changed into a prime (64604591) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 61480 + ... + 62521.

It is an arithmetic number, because the mean of its divisors is an integer number (16182261).

Almost surely, 2^64604521 is an apocalyptic number.

It is an amenable number.

64604521 is a deficient number, since it is larger than the sum of its proper divisors (124523).

64604521 is a wasteful number, since it uses less digits than its factorization.

64604521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124522.

The product of its (nonzero) digits is 5760, while the sum is 28.

The square root of 64604521 is about 8037.6937612726. The cubic root of 64604521 is about 401.2554740893.

The spelling of 64604521 in words is "sixty-four million, six hundred four thousand, five hundred twenty-one".