66194653680 has 80 divisors (see below), whose sum is σ = 228003814560. Its totient is φ = 17651907072.

The previous prime is 66194653663. The next prime is 66194653687. The reversal of 66194653680 is 8635649166.

66194653680 is a `hidden beast` number, since 6 + 61 + 9 + 46 + 536 + 8 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66194653687) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15320677 + ... + 15324996.

It is an arithmetic number, because the mean of its divisors is an integer number (2850047682).

Almost surely, 2^66194653680 is an apocalyptic number.

66194653680 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66194653680 is an abundant number, since it is smaller than the sum of its proper divisors (161809160880).

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

66194653680 is a wasteful number, since it uses less digits than its factorization.

66194653680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30645695 (or 30645683 counting only the distinct ones).

The product of its (nonzero) digits is 5598720, while the sum is 54.

The spelling of 66194653680 in words is "sixty-six billion, one hundred ninety-four million, six hundred fifty-three thousand, six hundred eighty".