66128243 has 8 divisors (see below), whose sum is σ = 69446688. Its totient is φ = 62846784.

The previous prime is 66128221. The next prime is 66128267. The reversal of 66128243 is 34282166.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66128243 - 2⁸ = 66127987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66128143) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5546 + ... + 12767.

It is an arithmetic number, because the mean of its divisors is an integer number (8680836).

Almost surely, 2^66128243 is an apocalyptic number.

66128243 is a deficient number, since it is larger than the sum of its proper divisors (3318445).

66128243 is a wasteful number, since it uses less digits than its factorization.

66128243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18493.

The product of its digits is 13824, while the sum is 32.

The square root of 66128243 is about 8131.9273853128. The cubic root of 66128243 is about 404.3855805635.

The spelling of 66128243 in words is "sixty-six million, one hundred twenty-eight thousand, two hundred forty-three".