66680813408 has 24 divisors (see below), whose sum is σ = 143212202280. Its totient is φ = 30309460480.

The previous prime is 66680813399. The next prime is 66680813453. The reversal of 66680813408 is 80431808666.

It is a happy number.

It is a congruent number.

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, 94716713 + ... + 94717416.

It is an arithmetic number, because the mean of its divisors is an integer number (5967175095).

Almost surely, 2^66680813408 is an apocalyptic number.

It is an amenable number.

66680813408 is an abundant number, since it is smaller than the sum of its proper divisors (76531388872).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66680813408 is a wasteful number, since it uses less digits than its factorization.

66680813408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 189434150 (or 189434142 counting only the distinct ones).

The product of its (nonzero) digits is 1327104, while the sum is 50.

It can be divided in two parts, 66680 and 813408, that added together give a palindrome (880088).

The spelling of 66680813408 in words is "sixty-six billion, six hundred eighty million, eight hundred thirteen thousand, four hundred eight".