166051399 has 2 divisors, whose sum is σ = 166051400. Its totient is φ = 166051398.

The previous prime is 166051397. The next prime is 166051409. The reversal of 166051399 is 993150661.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 166051399 - 2¹ = 166051397 is a prime.

Together with 166051397, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166051397) 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, 83025699 + 83025700.

It is an arithmetic number, because the mean of its divisors is an integer number (83025700).

Almost surely, 2^166051399 is an apocalyptic number.

166051399 is a deficient number, since it is larger than the sum of its proper divisors (1).

166051399 is an equidigital number, since it uses as much as digits as its factorization.

166051399 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 43740, while the sum is 40.

The square root of 166051399 is about 12886.0932403890. The cubic root of 166051399 is about 549.6431834387.

The spelling of 166051399 in words is "one hundred sixty-six million, fifty-one thousand, three hundred ninety-nine".