71778137688 has 160 divisors (see below), whose sum is σ = 206813122560. Its totient is φ = 23245548480.

The previous prime is 71778137663. The next prime is 71778137689. The reversal of 71778137688 is 88673187717.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71778137689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 5315281 + ... + 5328767.

It is an arithmetic number, because the mean of its divisors is an integer number (1292582016).

Almost surely, 2^71778137688 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 71778137688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (103406561280).

71778137688 is an abundant number, since it is smaller than the sum of its proper divisors (135034984872).

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

71778137688 is a wasteful number, since it uses less digits than its factorization.

71778137688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13739 (or 13726 counting only the distinct ones).

The product of its digits is 22127616, while the sum is 63.

The spelling of 71778137688 in words is "seventy-one billion, seven hundred seventy-eight million, one hundred thirty-seven thousand, six hundred eighty-eight".