61864621424640 has 720 divisors, whose sum is σ = 239024732375520. Its totient is φ = 14709549957120.

The previous prime is 61864621424633. The next prime is 61864621424713. The reversal of 61864621424640 is 4642412646816.

61864621424640 is a `hidden beast` number, since 6 + 1 + 8 + 6 + 4 + 621 + 4 + 2 + 4 + 6 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (720).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 238011550 + ... + 238271330.

It is an arithmetic number, because the mean of its divisors is an integer number (331978794966).

Almost surely, 2^{61864621424640} is an apocalyptic number.

61864621424640 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 61864621424640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (119512366187760).

61864621424640 is an abundant number, since it is smaller than the sum of its proper divisors (177160110950880).

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

61864621424640 is a wasteful number, since it uses less digits than its factorization.

61864621424640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 259856 (or 259827 counting only the distinct ones).

The product of its (nonzero) digits is 10616832, while the sum is 54.

The spelling of 61864621424640 in words is "sixty-one trillion, eight hundred sixty-four billion, six hundred twenty-one million, four hundred twenty-four thousand, six hundred forty".