66638553530664 has 32 divisors (see below), whose sum is σ = 166608535213440. Its totient is φ = 22211230992000.

The previous prime is 66638553530663. The next prime is 66638553530669. The reversal of 66638553530664 is 46603535583666.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 66638553530595 and 66638553530604.

It is not an unprimeable number, because it can be changed into a prime (66638553530663) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 100925637 + ... + 101583764.

It is an arithmetic number, because the mean of its divisors is an integer number (5206516725420).

Almost surely, 2^{66638553530664} is an apocalyptic number.

It is an amenable number.

66638553530664 is an abundant number, since it is smaller than the sum of its proper divisors (99969981682776).

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

66638553530664 is a wasteful number, since it uses less digits than its factorization.

66638553530664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 202523121 (or 202523117 counting only the distinct ones).

The product of its (nonzero) digits is 839808000, while the sum is 66.

The spelling of 66638553530664 in words is "sixty-six trillion, six hundred thirty-eight billion, five hundred fifty-three million, five hundred thirty thousand, six hundred sixty-four".