67978106658 has 128 divisors (see below), whose sum is σ = 191891773440. Its totient is φ = 17323450560.

The previous prime is 67978106629. The next prime is 67978106683. The reversal of 67978106658 is 85660187976.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 67978106595 and 67978106604.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 66141 + ... + 374607.

It is an arithmetic number, because the mean of its divisors is an integer number (1499154480).

Almost surely, 2^67978106658 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 67978106658, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95945886720).

67978106658 is an abundant number, since it is smaller than the sum of its proper divisors (123913666782).

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

67978106658 is a wasteful number, since it uses less digits than its factorization.

67978106658 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 308549 (or 308543 counting only the distinct ones).

The product of its (nonzero) digits is 30481920, while the sum is 63.

The spelling of 67978106658 in words is "sixty-seven billion, nine hundred seventy-eight million, one hundred six thousand, six hundred fifty-eight".