66172350653 has 2 divisors, whose sum is σ = 66172350654. Its totient is φ = 66172350652.

The previous prime is 66172350631. The next prime is 66172350679. The reversal of 66172350653 is 35605327166.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 62233784089 + 3938566564 = 249467^2 + 62758^2 .

It is a cyclic number.

It is not a de Polignac number, because 66172350653 - 2¹⁰ = 66172349629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66172350623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33086175326 + 33086175327.

It is an arithmetic number, because the mean of its divisors is an integer number (33086175327).

Almost surely, 2^66172350653 is an apocalyptic number.

It is an amenable number.

66172350653 is a deficient number, since it is larger than the sum of its proper divisors (1).

66172350653 is an equidigital number, since it uses as much as digits as its factorization.

66172350653 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 680400, while the sum is 44.

The spelling of 66172350653 in words is "sixty-six billion, one hundred seventy-two million, three hundred fifty thousand, six hundred fifty-three".