64543841620 has 12 divisors (see below), whose sum is σ = 135542067444. Its totient is φ = 25817536640.

The previous prime is 64543841539. The next prime is 64543841623. The reversal of 64543841620 is 2614834546.

It can be written as a sum of positive squares in 2 ways, for example, as 6537045904 + 58006795716 = 80852^2 + 240846^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64543841623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1613596021 + ... + 1613596060.

It is an arithmetic number, because the mean of its divisors is an integer number (11295172287).

Almost surely, 2^64543841620 is an apocalyptic number.

It is an amenable number.

64543841620 is an abundant number, since it is smaller than the sum of its proper divisors (70998225824).

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

64543841620 is a wasteful number, since it uses less digits than its factorization.

64543841620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3227192090 (or 3227192088 counting only the distinct ones).

The product of its (nonzero) digits is 552960, while the sum is 43.

The spelling of 64543841620 in words is "sixty-four billion, five hundred forty-three million, eight hundred forty-one thousand, six hundred twenty".