66291320532601 has 4 divisors (see below), whose sum is σ = 66291371841892. Its totient is φ = 66291269223312.

The previous prime is 66291320532583. The next prime is 66291320532607. The reversal of 66291320532601 is 10623502319266.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 36369053016976 + 29922267515625 = 6030676^2 + 5470125^2 .

It is a cyclic number.

It is not a de Polignac number, because 66291320532601 - 2⁷ = 66291320532473 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66291320532607) 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, 23665230 + ... + 26317783.

It is an arithmetic number, because the mean of its divisors is an integer number (16572842960473).

Almost surely, 2^{66291320532601} is an apocalyptic number.

It is an amenable number.

66291320532601 is a deficient number, since it is larger than the sum of its proper divisors (51309291).

66291320532601 is a wasteful number, since it uses less digits than its factorization.

66291320532601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51309290.

The product of its (nonzero) digits is 699840, while the sum is 46.

The spelling of 66291320532601 in words is "sixty-six trillion, two hundred ninety-one billion, three hundred twenty million, five hundred thirty-two thousand, six hundred one".