66758558951 has 4 divisors (see below), whose sum is σ = 76295495952. Its totient is φ = 57221621952.

The previous prime is 66758558857. The next prime is 66758558959. The reversal of 66758558951 is 15985585766.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 15985585766 = 2 ⋅7992792883.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66758558951 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 (66758558959) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4768468490 + ... + 4768468503.

It is an arithmetic number, because the mean of its divisors is an integer number (19073873988).

Almost surely, 2^66758558951 is an apocalyptic number.

66758558951 is a deficient number, since it is larger than the sum of its proper divisors (9536937001).

66758558951 is an equidigital number, since it uses as much as digits as its factorization.

66758558951 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9536937000.

The product of its digits is 90720000, while the sum is 65.

The spelling of 66758558951 in words is "sixty-six billion, seven hundred fifty-eight million, five hundred fifty-eight thousand, nine hundred fifty-one".