64520819 has 8 divisors (see below), whose sum is σ = 73446912. Its totient is φ = 56104840.

The previous prime is 64520803. The next prime is 64520857. The reversal of 64520819 is 91802546.

64520819 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 64520819 - 2⁴ = 64520803 is a prime.

It is a super-2 number, since 2×64520819² = 8325872168861522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (64520419) 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 7 ways as a sum of consecutive naturals, for example, 127259 + ... + 127764.

It is an arithmetic number, because the mean of its divisors is an integer number (9180864).

Almost surely, 2^64520819 is an apocalyptic number.

64520819 is a deficient number, since it is larger than the sum of its proper divisors (8926093).

64520819 is a wasteful number, since it uses less digits than its factorization.

64520819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255057.

The product of its (nonzero) digits is 17280, while the sum is 35.

The square root of 64520819 is about 8032.4852318570. The cubic root of 64520819 is about 401.0821095409.

The spelling of 64520819 in words is "sixty-four million, five hundred twenty thousand, eight hundred nineteen".