61644595822720 has 128 divisors (see below), whose sum is σ = 152546712652800. Its totient is φ = 23795952291840.

The previous prime is 61644595822697. The next prime is 61644595822753. The reversal of 61644595822720 is 2722859544616.

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

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2795142 + ... + 11449978.

It is an arithmetic number, because the mean of its divisors is an integer number (1191771192600).

Almost surely, 2^{61644595822720} 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 61644595822720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (76273356326400).

61644595822720 is an abundant number, since it is smaller than the sum of its proper divisors (90902116830080).

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

61644595822720 is a wasteful number, since it uses less digits than its factorization.

61644595822720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8655246 (or 8655234 counting only the distinct ones).

The product of its (nonzero) digits is 58060800, while the sum is 61.

The spelling of 61644595822720 in words is "sixty-one trillion, six hundred forty-four billion, five hundred ninety-five million, eight hundred twenty-two thousand, seven hundred twenty".