1205999 has 2 divisors, whose sum is σ = 1206000. Its totient is φ = 1205998.

The previous prime is 1205977. The next prime is 1206013. The reversal of 1205999 is 9995021.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1205999 - 2¹⁶ = 1140463 is a prime.

It is a Chen prime.

It is an Ulam number.

It is a plaindrome in base 16.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1205969) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 602999 + 603000.

It is an arithmetic number, because the mean of its divisors is an integer number (603000).

2^1205999 is an apocalyptic number.

1205999 is a deficient number, since it is larger than the sum of its proper divisors (1).

1205999 is an equidigital number, since it uses as much as digits as its factorization.

1205999 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7290, while the sum is 35.

The square root of 1205999 is about 1098.1798577647. The cubic root of 1205999 is about 106.4426428938.

The spelling of 1205999 in words is "one million, two hundred five thousand, nine hundred ninety-nine".