66125749 has 2 divisors, whose sum is σ = 66125750. Its totient is φ = 66125748.

The previous prime is 66125707. The next prime is 66125777. The reversal of 66125749 is 94752166.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 46144849 + 19980900 = 6793^2 + 4470^2 .

It is a cyclic number.

It is not a de Polignac number, because 66125749 - 2¹⁵ = 66092981 is a prime.

It is a super-2 number, since 2×66125749² = 8745229361622002, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66120749) 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, 33062874 + 33062875.

It is an arithmetic number, because the mean of its divisors is an integer number (33062875).

Almost surely, 2^66125749 is an apocalyptic number.

It is an amenable number.

66125749 is a deficient number, since it is larger than the sum of its proper divisors (1).

66125749 is an equidigital number, since it uses as much as digits as its factorization.

66125749 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 90720, while the sum is 40.

The square root of 66125749 is about 8131.7740376870. The cubic root of 66125749 is about 404.3804967533.

The spelling of 66125749 in words is "sixty-six million, one hundred twenty-five thousand, seven hundred forty-nine".