66749756615 has 32 divisors (see below), whose sum is σ = 84762685440. Its totient is φ = 50321606400.

The previous prime is 66749756597. The next prime is 66749756621. The reversal of 66749756615 is 51665794766.

It is not a de Polignac number, because 66749756615 - 2¹⁴ = 66749740231 is a prime.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 19590242 + ... + 19593648.

It is an arithmetic number, because the mean of its divisors is an integer number (2648833920).

Almost surely, 2^66749756615 is an apocalyptic number.

66749756615 is a deficient number, since it is larger than the sum of its proper divisors (18012928825).

66749756615 is a wasteful number, since it uses less digits than its factorization.

66749756615 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4463.

The product of its digits is 57153600, while the sum is 62.

The spelling of 66749756615 in words is "sixty-six billion, seven hundred forty-nine million, seven hundred fifty-six thousand, six hundred fifteen".