166603501 has 2 divisors, whose sum is σ = 166603502. Its totient is φ = 166603500.

The previous prime is 166603499. The next prime is 166603511. The reversal of 166603501 is 105306661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 154008100 + 12595401 = 12410^2 + 3549^2 .

It is a cyclic number.

It is not a de Polignac number, because 166603501 - 2¹ = 166603499 is a prime.

Together with 166603499, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 166603501.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166603511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83301750 + 83301751.

It is an arithmetic number, because the mean of its divisors is an integer number (83301751).

Almost surely, 2^166603501 is an apocalyptic number.

It is an amenable number.

166603501 is a deficient number, since it is larger than the sum of its proper divisors (1).

166603501 is an equidigital number, since it uses as much as digits as its factorization.

166603501 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3240, while the sum is 28.

The square root of 166603501 is about 12907.4978597713. The cubic root of 166603501 is about 550.2516765524.

The spelling of 166603501 in words is "one hundred sixty-six million, six hundred three thousand, five hundred one".