66189751 has 2 divisors, whose sum is σ = 66189752. Its totient is φ = 66189750.

The previous prime is 66189737. The next prime is 66189779. The reversal of 66189751 is 15798166.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66189751 - 2⁵ = 66189719 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66189698 and 66189707.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66189701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33094875 + 33094876.

It is an arithmetic number, because the mean of its divisors is an integer number (33094876).

Almost surely, 2^66189751 is an apocalyptic number.

66189751 is a deficient number, since it is larger than the sum of its proper divisors (1).

66189751 is an equidigital number, since it uses as much as digits as its factorization.

66189751 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 90720, while the sum is 43.

The square root of 66189751 is about 8135.7083895626. The cubic root of 66189751 is about 404.5109190444.

The spelling of 66189751 in words is "sixty-six million, one hundred eighty-nine thousand, seven hundred fifty-one".