66533710636021 has 4 divisors (see below), whose sum is σ = 67057598121472. Its totient is φ = 66009823150572.

The previous prime is 66533710636009. The next prime is 66533710636033. The reversal of 66533710636021 is 12063601733566.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (66533710636009) and next prime (66533710636033).

It is a cyclic number.

It is not a de Polignac number, because 66533710636021 - 2⁷ = 66533710635893 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 (66533710636061) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 261943742535 + ... + 261943742788.

It is an arithmetic number, because the mean of its divisors is an integer number (16764399530368).

Almost surely, 2^{66533710636021} is an apocalyptic number.

It is an amenable number.

66533710636021 is a deficient number, since it is larger than the sum of its proper divisors (523887485451).

66533710636021 is a wasteful number, since it uses less digits than its factorization.

66533710636021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 523887485450.

The product of its (nonzero) digits is 2449440, while the sum is 49.

The spelling of 66533710636021 in words is "sixty-six trillion, five hundred thirty-three billion, seven hundred ten million, six hundred thirty-six thousand, twenty-one".