66424157 has 4 divisors (see below), whose sum is σ = 66464220. Its totient is φ = 66384096.

The previous prime is 66424129. The next prime is 66424177. The reversal of 66424157 is 75142466.

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

It can be written as a sum of positive squares in 2 ways, for example, as 30591961 + 35832196 = 5531^2 + 5986^2 .

It is a cyclic number.

It is not a de Polignac number, because 66424157 - 2⁶ = 66424093 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66424177) 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, 17432 + ... + 20897.

It is an arithmetic number, because the mean of its divisors is an integer number (16616055).

Almost surely, 2^66424157 is an apocalyptic number.

It is an amenable number.

66424157 is a deficient number, since it is larger than the sum of its proper divisors (40063).

66424157 is a wasteful number, since it uses less digits than its factorization.

66424157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40062.

The product of its digits is 40320, while the sum is 35.

The square root of 66424157 is about 8150.1016558077. The cubic root of 66424157 is about 404.9878714043.

The spelling of 66424157 in words is "sixty-six million, four hundred twenty-four thousand, one hundred fifty-seven".