66316720 has 40 divisors (see below), whose sum is σ = 154655280. Its totient is φ = 26446080.

The previous prime is 66316697. The next prime is 66316753. The reversal of 66316720 is 2761366.

It is a tau number, because it is divible by the number of its divisors (40).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30055 + ... + 32185.

It is an arithmetic number, because the mean of its divisors is an integer number (3866382).

Almost surely, 2^66316720 is an apocalyptic number.

It is an amenable number.

66316720 is an abundant number, since it is smaller than the sum of its proper divisors (88338560).

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

66316720 is a wasteful number, since it uses less digits than its factorization.

66316720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2533 (or 2527 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 31.

The square root of 66316720 is about 8143.5078436752. The cubic root of 66316720 is about 404.7694058960.

The spelling of 66316720 in words is "sixty-six million, three hundred sixteen thousand, seven hundred twenty".