61661565060 has 96 divisors (see below), whose sum is σ = 175506186240. Its totient is φ = 16172886912.

The previous prime is 61661565059. The next prime is 61661565061. The reversal of 61661565060 is 6056516616.

It is an interprime number because it is at equal distance from previous prime (61661565059) and next prime (61661565061).

It is a super-3 number, since 3×61661565060³ (a number of 33 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (61661565061) 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, 1221889 + ... + 1271351.

It is an arithmetic number, because the mean of its divisors is an integer number (1828189440).

Almost surely, 2^61661565060 is an apocalyptic number.

61661565060 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 61661565060, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (87753093120).

61661565060 is an abundant number, since it is smaller than the sum of its proper divisors (113844621180).

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

61661565060 is a wasteful number, since it uses less digits than its factorization.

61661565060 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49817 (or 49815 counting only the distinct ones).

The product of its (nonzero) digits is 194400, while the sum is 42.

The spelling of 61661565060 in words is "sixty-one billion, six hundred sixty-one million, five hundred sixty-five thousand, sixty".