68644739520 has 784 divisors, whose sum is σ = 283147788288. Its totient is φ = 15519651840.

The previous prime is 68644739491. The next prime is 68644739521. The reversal of 68644739520 is 2593744686.

68644739520 is a `hidden beast` number, since 6 + 8 + 6 + 44 + 73 + 9 + 520 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68644739521) by changing a digit.

It is a polite number, since it can be written in 111 ways as a sum of consecutive naturals, for example, 207385755 + ... + 207386085.

Almost surely, 2^68644739520 is an apocalyptic number.

68644739520 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 68644739520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (141573894144).

68644739520 is an abundant number, since it is smaller than the sum of its proper divisors (214503048768).

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

68644739520 is a wasteful number, since it uses less digits than its factorization.

68644739520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 500 (or 475 counting only the distinct ones).

The product of its (nonzero) digits is 8709120, while the sum is 54.

The spelling of 68644739520 in words is "sixty-eight billion, six hundred forty-four million, seven hundred thirty-nine thousand, five hundred twenty".