166611559 has 2 divisors, whose sum is σ = 166611560. Its totient is φ = 166611558.

The previous prime is 166611547. The next prime is 166611677. The reversal of 166611559 is 955116661.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 166611559 - 2⁵ = 166611527 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166611539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83305779 + 83305780.

It is an arithmetic number, because the mean of its divisors is an integer number (83305780).

Almost surely, 2^166611559 is an apocalyptic number.

166611559 is a deficient number, since it is larger than the sum of its proper divisors (1).

166611559 is an equidigital number, since it uses as much as digits as its factorization.

166611559 is an evil number, because the sum of its binary digits is even.

The product of its digits is 48600, while the sum is 40.

The square root of 166611559 is about 12907.8100001511. The cubic root of 166611559 is about 550.2605476275.

It can be divided in two parts, 1666 and 11559, that added together give a square (13225 = 115²).

The spelling of 166611559 in words is "one hundred sixty-six million, six hundred eleven thousand, five hundred fifty-nine".