66518046621 has 144 divisors (see below), whose sum is σ = 110069668800. Its totient is φ = 38653056000.

The previous prime is 66518046613. The next prime is 66518046677. The reversal of 66518046621 is 12664081566.

66518046621 is a `hidden beast` number, since 6 + 6 + 5 + 18 + 0 + 4 + 6 + 621 = 666.

It is not a de Polignac number, because 66518046621 - 2³ = 66518046613 is a prime.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66518046601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 371609110 + ... + 371609288.

It is an arithmetic number, because the mean of its divisors is an integer number (764372700).

Almost surely, 2^66518046621 is an apocalyptic number.

It is an amenable number.

66518046621 is a deficient number, since it is larger than the sum of its proper divisors (43551622179).

66518046621 is a wasteful number, since it uses less digits than its factorization.

66518046621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 412 (or 396 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 45.

The spelling of 66518046621 in words is "sixty-six billion, five hundred eighteen million, forty-six thousand, six hundred twenty-one".