64641599 has 16 divisors (see below), whose sum is σ = 76412160. Its totient is φ = 54015360.

The previous prime is 64641593. The next prime is 64641607. The reversal of 64641599 is 99514646.

It is a Cunningham number, because it is equal to 8040²-1.

It is a cyclic number.

It is not a de Polignac number, because 64641599 - 2⁴ = 64641583 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64641593) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4022 + ... + 12060.

It is an arithmetic number, because the mean of its divisors is an integer number (4775760).

Almost surely, 2^64641599 is an apocalyptic number.

64641599 is a deficient number, since it is larger than the sum of its proper divisors (11770561).

64641599 is a wasteful number, since it uses less digits than its factorization.

64641599 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8110.

The product of its digits is 233280, while the sum is 44.

The square root of 64641599 is about 8039.9999378109. Note that the first 4 decimals coincide. The cubic root of 64641599 is about 401.3322226147.

The spelling of 64641599 in words is "sixty-four million, six hundred forty-one thousand, five hundred ninety-nine".