166642519 has 2 divisors, whose sum is σ = 166642520. Its totient is φ = 166642518.

The previous prime is 166642493. The next prime is 166642571. The reversal of 166642519 is 915246661.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166642519 is a prime.

It is a super-2 number, since 2×166642519² = 55539458277330722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166642219) 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, 83321259 + 83321260.

It is an arithmetic number, because the mean of its divisors is an integer number (83321260).

Almost surely, 2^166642519 is an apocalyptic number.

166642519 is a deficient number, since it is larger than the sum of its proper divisors (1).

166642519 is an equidigital number, since it uses as much as digits as its factorization.

166642519 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 77760, while the sum is 40.

The square root of 166642519 is about 12909.0092183715. The cubic root of 166642519 is about 550.2946289192.

The spelling of 166642519 in words is "one hundred sixty-six million, six hundred forty-two thousand, five hundred nineteen".