166667899 has 2 divisors, whose sum is σ = 166667900. Its totient is φ = 166667898.

The previous prime is 166667887. The next prime is 166667947. The reversal of 166667899 is 998766661.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 166667899 - 2⁷ = 166667771 is a prime.

It is a plaindrome in base 10.

It is not a weakly prime, because it can be changed into another prime (166667819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83333949 + 83333950.

It is an arithmetic number, because the mean of its divisors is an integer number (83333950).

Almost surely, 2^166667899 is an apocalyptic number.

166667899 is a deficient number, since it is larger than the sum of its proper divisors (1).

166667899 is an equidigital number, since it uses as much as digits as its factorization.

166667899 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5878656, while the sum is 58.

The square root of 166667899 is about 12909.9922153346. The cubic root of 166667899 is about 550.3225645041.

The spelling of 166667899 in words is "one hundred sixty-six million, six hundred sixty-seven thousand, eight hundred ninety-nine".