61646936064 has 576 divisors, whose sum is σ = 207048441600. Its totient is φ = 16213671936.

The previous prime is 61646936047. The next prime is 61646936107. The reversal of 61646936064 is 46063964616.

It is a junction number, because it is equal to n+sod(n) for n = 61646935998 and 61646936016.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 200804199 + ... + 200804505.

It is an arithmetic number, because the mean of its divisors is an integer number (359459100).

Almost surely, 2^61646936064 is an apocalyptic number.

61646936064 is a gapful number since it is divisible by the number (64) 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 61646936064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (103524220800).

61646936064 is an abundant number, since it is smaller than the sum of its proper divisors (145401505536).

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

61646936064 is a wasteful number, since it uses less digits than its factorization.

61646936064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 398 (or 371 counting only the distinct ones).

The product of its (nonzero) digits is 3359232, while the sum is 51.

The spelling of 61646936064 in words is "sixty-one billion, six hundred forty-six million, nine hundred thirty-six thousand, sixty-four".