64521670 has 64 divisors (see below), whose sum is σ = 126904320. Its totient is φ = 23557248.

The previous prime is 64521641. The next prime is 64521671. The reversal of 64521670 is 7612546.

It is a happy number.

64521670 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64521671) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 816691 + ... + 816769.

It is an arithmetic number, because the mean of its divisors is an integer number (1982880).

Almost surely, 2^64521670 is an apocalyptic number.

64521670 is a deficient number, since it is larger than the sum of its proper divisors (62382650).

64521670 is a wasteful number, since it uses less digits than its factorization.

64521670 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 229.

The product of its (nonzero) digits is 10080, while the sum is 31.

The square root of 64521670 is about 8032.5382040797. The cubic root of 64521670 is about 401.0838728961.

The spelling of 64521670 in words is "sixty-four million, five hundred twenty-one thousand, six hundred seventy".