66628751 has 8 divisors (see below), whose sum is σ = 77767680. Its totient is φ = 55894968.

The previous prime is 66628739. The next prime is 66628781. The reversal of 66628751 is 15782666.

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 66628751 - 2¹⁴ = 66612367 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66628699 and 66628708.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66628781) 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, 100931 + ... + 101588.

It is an arithmetic number, because the mean of its divisors is an integer number (9720960).

Almost surely, 2^66628751 is an apocalyptic number.

66628751 is a deficient number, since it is larger than the sum of its proper divisors (11138929).

66628751 is a wasteful number, since it uses less digits than its factorization.

66628751 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 202573.

The product of its digits is 120960, while the sum is 41.

The square root of 66628751 is about 8162.6436281391. The cubic root of 66628751 is about 405.4032482129.

The spelling of 66628751 in words is "sixty-six million, six hundred twenty-eight thousand, seven hundred fifty-one".