65766939920 has 80 divisors (see below), whose sum is σ = 167352913728. Its totient is φ = 23837253120.

The previous prime is 65766939919. The next prime is 65766939949. The reversal of 65766939920 is 2993966756.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-3 number, since 3×65766939920³ (a number of 33 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 148442 + ... + 391878.

Almost surely, 2^65766939920 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 65766939920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (83676456864).

65766939920 is an abundant number, since it is smaller than the sum of its proper divisors (101585973808).

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

65766939920 is a wasteful number, since it uses less digits than its factorization.

65766939920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 243768 (or 243762 counting only the distinct ones).

The product of its (nonzero) digits is 33067440, while the sum is 62.

It can be divided in two parts, 6576 and 6939920, that added together give a palindrome (6946496).

The spelling of 65766939920 in words is "sixty-five billion, seven hundred sixty-six million, nine hundred thirty-nine thousand, nine hundred twenty".