68661773540 has 24 divisors (see below), whose sum is σ = 145617349752. Its totient is φ = 27192780800.

The previous prime is 68661773513. The next prime is 68661773549. The reversal of 68661773540 is 4537716686.

It can be written as a sum of positive squares in 4 ways, for example, as 8188078144 + 60473695396 = 90488^2 + 245914^2 .

It is not an unprimeable number, because it can be changed into a prime (68661773549) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16993469 + ... + 16997508.

It is an arithmetic number, because the mean of its divisors is an integer number (6067389573).

Almost surely, 2^68661773540 is an apocalyptic number.

It is an amenable number.

68661773540 is an abundant number, since it is smaller than the sum of its proper divisors (76955576212).

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

68661773540 is a wasteful number, since it uses less digits than its factorization.

68661773540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33991087 (or 33991085 counting only the distinct ones).

The product of its (nonzero) digits is 5080320, while the sum is 53.

The spelling of 68661773540 in words is "sixty-eight billion, six hundred sixty-one million, seven hundred seventy-three thousand, five hundred forty".