65780471988 has 216 divisors, whose sum is σ = 213905240640. Its totient is φ = 16851421440.

The previous prime is 65780471951. The next prime is 65780472001. The reversal of 65780471988 is 88917408756.

65780471988 is a `hidden beast` number, since 6 + 5 + 7 + 80 + 471 + 9 + 88 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1393273 + ... + 1439711.

It is an arithmetic number, because the mean of its divisors is an integer number (990302040).

Almost surely, 2^65780471988 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 65780471988, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106952620320).

65780471988 is an abundant number, since it is smaller than the sum of its proper divisors (148124768652).

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

65780471988 is a wasteful number, since it uses less digits than its factorization.

65780471988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46547 (or 46535 counting only the distinct ones).

The product of its (nonzero) digits is 27095040, while the sum is 63.

The spelling of 65780471988 in words is "sixty-five billion, seven hundred eighty million, four hundred seventy-one thousand, nine hundred eighty-eight".