61685944321600 has 189 divisors, whose sum is σ = 158690885653027. Its totient is φ = 23598814074880.

The previous prime is 61685944321511. The next prime is 61685944321613. The reversal of 61685944321600 is 612344958616.

The square root of 61685944321600 is 7854040.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 5228393218624 + 56457551102976 = 2286568^2 + 7513824^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 7225712532 + ... + 7225721068.

Almost surely, 2^{61685944321600} is an apocalyptic number.

61685944321600 is the 7854040-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61685944321600

61685944321600 is an abundant number, since it is smaller than the sum of its proper divisors (97004941331427).

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

61685944321600 is an frugal number, since it uses more digits than its factorization.

61685944321600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17142 (or 8567 counting only the distinct ones).

The product of its (nonzero) digits is 7464960, while the sum is 55.

The spelling of 61685944321600 in words is "sixty-one trillion, six hundred eighty-five billion, nine hundred forty-four million, three hundred twenty-one thousand, six hundred".