66500791 has 12 divisors (see below), whose sum is σ = 78074040. Its totient is φ = 56473200.

The previous prime is 66500789. The next prime is 66500807. The reversal of 66500791 is 19700566.

It is not a de Polignac number, because 66500791 - 2¹ = 66500789 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66500771) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 885 + ... + 11566.

It is an arithmetic number, because the mean of its divisors is an integer number (6506170).

Almost surely, 2^66500791 is an apocalyptic number.

66500791 is a deficient number, since it is larger than the sum of its proper divisors (11573249).

66500791 is a wasteful number, since it uses less digits than its factorization.

66500791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12574 (or 12567 counting only the distinct ones).

The product of its (nonzero) digits is 11340, while the sum is 34.

The square root of 66500791 is about 8154.8017143276. The cubic root of 66500791 is about 405.1435572981.

The spelling of 66500791 in words is "sixty-six million, five hundred thousand, seven hundred ninety-one".