61664982720 has 448 divisors, whose sum is σ = 218999531520. Its totient is φ = 14573977600.

The previous prime is 61664982689. The next prime is 61664982727. The reversal of 61664982720 is 2728946616.

61664982720 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (61664982727) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 133763290 + ... + 133763750.

It is an arithmetic number, because the mean of its divisors is an integer number (488838240).

Almost surely, 2^61664982720 is an apocalyptic number.

61664982720 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61664982720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (109499765760).

61664982720 is an abundant number, since it is smaller than the sum of its proper divisors (157334548800).

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

61664982720 is a wasteful number, since it uses less digits than its factorization.

61664982720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 784 (or 774 counting only the distinct ones).

The product of its (nonzero) digits is 1741824, while the sum is 51.

The spelling of 61664982720 in words is "sixty-one billion, six hundred sixty-four million, nine hundred eighty-two thousand, seven hundred twenty".