66411716021 has 8 divisors (see below), whose sum is σ = 75948115200. Its totient is φ = 56887569648.

The previous prime is 66411715969. The next prime is 66411716029. The reversal of 66411716021 is 12061711466.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 66411716021 - 2²⁶ = 66344607157 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66411716029) 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 7 ways as a sum of consecutive naturals, for example, 3051581 + ... + 3073266.

It is an arithmetic number, because the mean of its divisors is an integer number (9493514400).

Almost surely, 2^66411716021 is an apocalyptic number.

It is an amenable number.

66411716021 is a deficient number, since it is larger than the sum of its proper divisors (9536399179).

66411716021 is a wasteful number, since it uses less digits than its factorization.

66411716021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6126403.

The product of its (nonzero) digits is 12096, while the sum is 35.

The spelling of 66411716021 in words is "sixty-six billion, four hundred eleven million, seven hundred sixteen thousand, twenty-one".