66415870786 has 12 divisors (see below), whose sum is σ = 100356351858. Its totient is φ = 32965523072.

The previous prime is 66415870769. The next prime is 66415870889. The reversal of 66415870786 is 68707851466.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 52223675625 + 14192195161 = 228525^2 + 119131^2 .

It is a super-2 number, since 2×66415870786² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 66415870786.

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 5 ways as a sum of consecutive naturals, for example, 847111 + ... + 922186.

Almost surely, 2^66415870786 is an apocalyptic number.

66415870786 is a deficient number, since it is larger than the sum of its proper divisors (33940481072).

66415870786 is a wasteful number, since it uses less digits than its factorization.

66415870786 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1769573 (or 1769436 counting only the distinct ones).

The product of its (nonzero) digits is 13547520, while the sum is 58.

The spelling of 66415870786 in words is "sixty-six billion, four hundred fifteen million, eight hundred seventy thousand, seven hundred eighty-six".