61644616344 has 48 divisors (see below), whose sum is σ = 171466451520. Its totient is φ = 19992847680.

The previous prime is 61644616333. The next prime is 61644616349. The reversal of 61644616344 is 44361644616.

It is a happy number.

61644616344 is a `hidden beast` number, since 6 + 1 + 6 + 4 + 4 + 6 + 1 + 634 + 4 = 666.

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 61644616344.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61644616349) 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 11 ways as a sum of consecutive naturals, for example, 11567272 + ... + 11572599.

It is an arithmetic number, because the mean of its divisors is an integer number (3572217740).

Almost surely, 2^61644616344 is an apocalyptic number.

It is an amenable number.

61644616344 is an abundant number, since it is smaller than the sum of its proper divisors (109821835176).

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

61644616344 is a wasteful number, since it uses less digits than its factorization.

61644616344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23139920 (or 23139913 counting only the distinct ones).

The product of its digits is 995328, while the sum is 45.

The spelling of 61644616344 in words is "sixty-one billion, six hundred forty-four million, six hundred sixteen thousand, three hundred forty-four".