61643584385 has 24 divisors (see below), whose sum is σ = 75545591976. Its totient is φ = 48286883840.

The previous prime is 61643584369. The next prime is 61643584391. The reversal of 61643584385 is 58348534616.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 24852891904 + 36790692481 = 157648^2 + 191809^2 .

It is not a de Polignac number, because 61643584385 - 2⁴ = 61643584369 is a prime.

It is a hoax number, since the sum of its digits (53) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 4466195 + ... + 4479975.

It is an arithmetic number, because the mean of its divisors is an integer number (3147732999).

Almost surely, 2^61643584385 is an apocalyptic number.

It is an amenable number.

61643584385 is a deficient number, since it is larger than the sum of its proper divisors (13902007591).

61643584385 is a wasteful number, since it uses less digits than its factorization.

61643584385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14161 (or 14102 counting only the distinct ones).

The product of its digits is 8294400, while the sum is 53.

The spelling of 61643584385 in words is "sixty-one billion, six hundred forty-three million, five hundred eighty-four thousand, three hundred eighty-five".