66755251 has 4 divisors (see below), whose sum is σ = 67505400. Its totient is φ = 66005104.

The previous prime is 66755239. The next prime is 66755261. The reversal of 66755251 is 15255766.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66755251 - 2⁵ = 66755219 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 66755251.

It is not an unprimeable number, because it can be changed into a prime (66755261) 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 3 ways as a sum of consecutive naturals, for example, 374941 + ... + 375118.

It is an arithmetic number, because the mean of its divisors is an integer number (16876350).

Almost surely, 2^66755251 is an apocalyptic number.

66755251 is a deficient number, since it is larger than the sum of its proper divisors (750149).

66755251 is an equidigital number, since it uses as much as digits as its factorization.

66755251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 750148.

The product of its digits is 63000, while the sum is 37.

The square root of 66755251 is about 8170.3886688456. The cubic root of 66755251 is about 405.6596494863.

It can be divided in two parts, 6 and 6755251, that multiplied together give a triangular number (40531506 = T₉₀₀₃).

The spelling of 66755251 in words is "sixty-six million, seven hundred fifty-five thousand, two hundred fifty-one".