61686580 has 12 divisors (see below), whose sum is σ = 129541860. Its totient is φ = 24674624.

The previous prime is 61686551. The next prime is 61686589. The reversal of 61686580 is 8568616.

It is a happy number.

61686580 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 38588944 + 23097636 = 6212^2 + 4806^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61686589) 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 3 ways as a sum of consecutive naturals, for example, 1542145 + ... + 1542184.

It is an arithmetic number, because the mean of its divisors is an integer number (10795155).

Almost surely, 2^61686580 is an apocalyptic number.

It is an amenable number.

61686580 is an abundant number, since it is smaller than the sum of its proper divisors (67855280).

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

61686580 is a wasteful number, since it uses less digits than its factorization.

61686580 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3084338 (or 3084336 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 40.

The square root of 61686580 is about 7854.0804681388. The cubic root of 61686580 is about 395.1211079798.

The spelling of 61686580 in words is "sixty-one million, six hundred eighty-six thousand, five hundred eighty".