166690019 has 2 divisors, whose sum is σ = 166690020. Its totient is φ = 166690018.

The previous prime is 166690009. The next prime is 166690031. The reversal of 166690019 is 910096661.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166690019 is a prime.

It is a super-2 number, since 2×166690019² = 55571124868440722, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (166690009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83345009 + 83345010.

It is an arithmetic number, because the mean of its divisors is an integer number (83345010).

Almost surely, 2^166690019 is an apocalyptic number.

166690019 is a deficient number, since it is larger than the sum of its proper divisors (1).

166690019 is an equidigital number, since it uses as much as digits as its factorization.

166690019 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17496, while the sum is 38.

The square root of 166690019 is about 12910.8488876603. The cubic root of 166690019 is about 550.3469095174.

The spelling of 166690019 in words is "one hundred sixty-six million, six hundred ninety thousand, nineteen".