66428751 has 8 divisors (see below), whose sum is σ = 88637184. Its totient is φ = 44253080.

The previous prime is 66428711. The next prime is 66428767. The reversal of 66428751 is 15782466.

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 66428751 - 2¹⁰ = 66427727 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66428701) 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 in 7 ways as a sum of consecutive naturals, for example, 2985 + ... + 11906.

It is an arithmetic number, because the mean of its divisors is an integer number (11079648).

Almost surely, 2^66428751 is an apocalyptic number.

66428751 is a deficient number, since it is larger than the sum of its proper divisors (22208433).

66428751 is a wasteful number, since it uses less digits than its factorization.

66428751 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16381.

The product of its digits is 80640, while the sum is 39.

The square root of 66428751 is about 8150.3834879102. The cubic root of 66428751 is about 404.9972077235.

The spelling of 66428751 in words is "sixty-six million, four hundred twenty-eight thousand, seven hundred fifty-one".