66427257 has 16 divisors (see below), whose sum is σ = 97711488. Its totient is φ = 39880320.

The previous prime is 66427213. The next prime is 66427259. The reversal of 66427257 is 75272466.

It is a happy number.

It is not a de Polignac number, because 66427257 - 2²⁰ = 65378681 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (66427259) 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 15 ways as a sum of consecutive naturals, for example, 19173 + ... + 22370.

It is an arithmetic number, because the mean of its divisors is an integer number (6106968).

Almost surely, 2^66427257 is an apocalyptic number.

It is an amenable number.

66427257 is a deficient number, since it is larger than the sum of its proper divisors (31284231).

66427257 is a wasteful number, since it uses less digits than its factorization.

66427257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41600.

The product of its digits is 141120, while the sum is 39.

The square root of 66427257 is about 8150.2918352658. The cubic root of 66427257 is about 404.9941715363.

The spelling of 66427257 in words is "sixty-six million, four hundred twenty-seven thousand, two hundred fifty-seven".