66748791 has 8 divisors (see below), whose sum is σ = 90217840. Its totient is φ = 43889472.

The previous prime is 66748757. The next prime is 66748793. The reversal of 66748791 is 19784766.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 66748791 - 2⁶ = 66748727 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 66748791.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66748793) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 152176 + ... + 152613.

It is an arithmetic number, because the mean of its divisors is an integer number (11277230).

Almost surely, 2^66748791 is an apocalyptic number.

66748791 is a deficient number, since it is larger than the sum of its proper divisors (23469049).

66748791 is a wasteful number, since it uses less digits than its factorization.

66748791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 304865.

The product of its digits is 508032, while the sum is 48.

The square root of 66748791 is about 8169.9933292506. The cubic root of 66748791 is about 405.6465636449.

The spelling of 66748791 in words is "sixty-six million, seven hundred forty-eight thousand, seven hundred ninety-one".