61711566720 has 256 divisors, whose sum is σ = 211392633600. Its totient is φ = 15256682496.

The previous prime is 61711566713. The next prime is 61711566727. The reversal of 61711566720 is 2766511716.

61711566720 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (61711566713) and next prime (61711566727).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61711566727) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2172771 + ... + 2200989.

It is an arithmetic number, because the mean of its divisors is an integer number (825752475).

Almost surely, 2^61711566720 is an apocalyptic number.

61711566720 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 61711566720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (105696316800).

61711566720 is an abundant number, since it is smaller than the sum of its proper divisors (149681066880).

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

61711566720 is a wasteful number, since it uses less digits than its factorization.

61711566720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28325 (or 28313 counting only the distinct ones).

The product of its (nonzero) digits is 105840, while the sum is 42.

The spelling of 61711566720 in words is "sixty-one billion, seven hundred eleven million, five hundred sixty-six thousand, seven hundred twenty".