66715992 has 96 divisors (see below), whose sum is σ = 217401600. Its totient is φ = 18055872.

The previous prime is 66715967. The next prime is 66716003. The reversal of 66715992 is 29951766.

It is a happy number.

It is a congruent number.

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, 6093 + ... + 13059.

It is an arithmetic number, because the mean of its divisors is an integer number (2264600).

Almost surely, 2^66715992 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 66715992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (108700800).

66715992 is an abundant number, since it is smaller than the sum of its proper divisors (150685608).

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

66715992 is a wasteful number, since it uses less digits than its factorization.

66715992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7005 (or 6998 counting only the distinct ones).

The product of its digits is 204120, while the sum is 45.

The square root of 66715992 is about 8167.9857982247. The cubic root of 66715992 is about 405.5801105988.

The spelling of 66715992 in words is "sixty-six million, seven hundred fifteen thousand, nine hundred ninety-two".