68121815040 has 288 divisors, whose sum is σ = 241136663040. Its totient is φ = 17778180096.

The previous prime is 68121815029. The next prime is 68121815059. The reversal of 68121815040 is 4051812186.

68121815040 is a `hidden beast` number, since 68 + 12 + 1 + 81 + 504 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 68121814986 and 68121815004.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4323657 + ... + 4339383.

It is an arithmetic number, because the mean of its divisors is an integer number (837280080).

Almost surely, 2^68121815040 is an apocalyptic number.

68121815040 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 68121815040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (120568331520).

68121815040 is an abundant number, since it is smaller than the sum of its proper divisors (173014848000).

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

68121815040 is a wasteful number, since it uses less digits than its factorization.

68121815040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15807 (or 15784 counting only the distinct ones).

The product of its (nonzero) digits is 15360, while the sum is 36.

The spelling of 68121815040 in words is "sixty-eight billion, one hundred twenty-one million, eight hundred fifteen thousand, forty".