66680421853 has 16 divisors (see below), whose sum is σ = 70535646720. Its totient is φ = 62860524336.

The previous prime is 66680421827. The next prime is 66680421887. The reversal of 66680421853 is 35812408666.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 66680421853 - 2⁹ = 66680421341 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66680421797 and 66680421806.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66680421803) 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, 3306226 + ... + 3326332.

It is an arithmetic number, because the mean of its divisors is an integer number (4408477920).

Almost surely, 2^66680421853 is an apocalyptic number.

It is an amenable number.

66680421853 is a deficient number, since it is larger than the sum of its proper divisors (3855224867).

66680421853 is a wasteful number, since it uses less digits than its factorization.

66680421853 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20976.

The product of its (nonzero) digits is 1658880, while the sum is 49.

The spelling of 66680421853 in words is "sixty-six billion, six hundred eighty million, four hundred twenty-one thousand, eight hundred fifty-three".