166139983 has 2 divisors, whose sum is σ = 166139984. Its totient is φ = 166139982.

The previous prime is 166139969. The next prime is 166139999. The reversal of 166139983 is 389931661.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166139983 is a prime.

It is a super-3 number, since 3×166139983³ (a number of 26 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166139903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83069991 + 83069992.

It is an arithmetic number, because the mean of its divisors is an integer number (83069992).

Almost surely, 2^166139983 is an apocalyptic number.

166139983 is a deficient number, since it is larger than the sum of its proper divisors (1).

166139983 is an equidigital number, since it uses as much as digits as its factorization.

166139983 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 209952, while the sum is 46.

The square root of 166139983 is about 12889.5299759146. The cubic root of 166139983 is about 549.7409060644.

The spelling of 166139983 in words is "one hundred sixty-six million, one hundred thirty-nine thousand, nine hundred eighty-three".