61685120 has 128 divisors (see below), whose sum is σ = 172584000. Its totient is φ = 21073920.

The previous prime is 61685111. The next prime is 61685159. The reversal of 61685120 is 2158616.

It is a happy number.

61685120 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 219380 + ... + 219660.

Almost surely, 2^61685120 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 61685120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86292000).

61685120 is an abundant number, since it is smaller than the sum of its proper divisors (110898880).

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

61685120 is an equidigital number, since it uses as much as digits as its factorization.

61685120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 321 (or 295 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 29.

The square root of 61685120 is about 7853.9875222717. The cubic root of 61685120 is about 395.1179907088.

It can be divided in two parts, 616 and 85120, that multiplied together give a triangular number (52433920 = T₁₀₂₄₀).

The spelling of 61685120 in words is "sixty-one million, six hundred eighty-five thousand, one hundred twenty".