66814014664 has 16 divisors (see below), whose sum is σ = 125286368220. Its totient is φ = 33404316480.

The previous prime is 66814014649. The next prime is 66814014719. The reversal of 66814014664 is 46641041866.

It can be written as a sum of positive squares in 2 ways, for example, as 44121002500 + 22693012164 = 210050^2 + 150642^2 .

It is a super-2 number, since 2×66814014664² (a number of 22 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 228807 + ... + 431254.

Almost surely, 2^66814014664 is an apocalyptic number.

It is an amenable number.

66814014664 is a deficient number, since it is larger than the sum of its proper divisors (58472353556).

66814014664 is a wasteful number, since it uses less digits than its factorization.

66814014664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 672720 (or 672716 counting only the distinct ones).

The product of its (nonzero) digits is 663552, while the sum is 46.

The spelling of 66814014664 in words is "sixty-six billion, eight hundred fourteen million, fourteen thousand, six hundred sixty-four".