61666830620 has 48 divisors (see below), whose sum is σ = 132843176928. Its totient is φ = 24032870400.

The previous prime is 61666830613. The next prime is 61666830683. The reversal of 61666830620 is 2603866616.

It is a congruent number.

It is an unprimeable number.

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, 255452 + ... + 434268.

It is an arithmetic number, because the mean of its divisors is an integer number (2767566186).

Almost surely, 2^61666830620 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61666830620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (66421588464).

61666830620 is an abundant number, since it is smaller than the sum of its proper divisors (71176346308).

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

61666830620 is a wasteful number, since it uses less digits than its factorization.

61666830620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 179270 (or 179268 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 44.

The spelling of 61666830620 in words is "sixty-one billion, six hundred sixty-six million, eight hundred thirty thousand, six hundred twenty".