166806708553 has 2 divisors, whose sum is σ = 166806708554. Its totient is φ = 166806708552.

The previous prime is 166806708479. The next prime is 166806708581. The reversal of 166806708553 is 355807608661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 127961452089 + 38845256464 = 357717^2 + 197092^2 .

It is a cyclic number.

It is not a de Polignac number, because 166806708553 - 2²¹ = 166804611401 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 166806708494 and 166806708503.

It is not a weakly prime, because it can be changed into another prime (166806708353) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83403354276 + 83403354277.

It is an arithmetic number, because the mean of its divisors is an integer number (83403354277).

Almost surely, 2^166806708553 is an apocalyptic number.

It is an amenable number.

166806708553 is a deficient number, since it is larger than the sum of its proper divisors (1).

166806708553 is an equidigital number, since it uses as much as digits as its factorization.

166806708553 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7257600, while the sum is 55.

The spelling of 166806708553 in words is "one hundred sixty-six billion, eight hundred six million, seven hundred eight thousand, five hundred fifty-three".