66746652021 has 40 divisors (see below), whose sum is σ = 114150006080. Its totient is φ = 38074655232.

The previous prime is 66746652019. The next prime is 66746652059. The reversal of 66746652021 is 12025664766.

66746652021 is a `hidden beast` number, since 6 + 67 + 4 + 66 + 520 + 2 + 1 = 666.

It is not a de Polignac number, because 66746652021 - 2¹ = 66746652019 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 Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66746652221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 225150 + ... + 429168.

It is an arithmetic number, because the mean of its divisors is an integer number (2853750152).

Almost surely, 2^66746652021 is an apocalyptic number.

It is an amenable number.

66746652021 is a deficient number, since it is larger than the sum of its proper divisors (47403354059).

66746652021 is a wasteful number, since it uses less digits than its factorization.

66746652021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204615 (or 204606 counting only the distinct ones).

The product of its (nonzero) digits is 725760, while the sum is 45.

The spelling of 66746652021 in words is "sixty-six billion, seven hundred forty-six million, six hundred fifty-two thousand, twenty-one".