66840753 has 32 divisors (see below), whose sum is σ = 110073600. Its totient is φ = 35938560.

The previous prime is 66840751. The next prime is 66840757. The reversal of 66840753 is 35704866.

It is not a de Polignac number, because 66840753 - 2¹ = 66840751 is a prime.

It is a super-3 number, since 3×66840753³ (a number of 24 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (66840751) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 15583 + ... + 19403.

It is an arithmetic number, because the mean of its divisors is an integer number (3439800).

Almost surely, 2^66840753 is an apocalyptic number.

It is an amenable number.

66840753 is a deficient number, since it is larger than the sum of its proper divisors (43232847).

66840753 is a wasteful number, since it uses less digits than its factorization.

66840753 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3862 (or 3848 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 39.

The square root of 66840753 is about 8175.6194260741. The cubic root of 66840753 is about 405.8327690186.

The spelling of 66840753 in words is "sixty-six million, eight hundred forty thousand, seven hundred fifty-three".