999091 has 2 divisors, whose sum is σ = 999092. Its totient is φ = 999090.

The previous prime is 999083. The next prime is 999101. The reversal of 999091 is 190999.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 999091 - 2³ = 999083 is a prime.

It is a Chen prime.

999091 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 999091.

It is not a weakly prime, because it can be changed into another prime (999491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499545 + 499546.

It is an arithmetic number, because the mean of its divisors is an integer number (499546).

2⁹⁹⁹⁰⁹¹ is an apocalyptic number.

999091 is a deficient number, since it is larger than the sum of its proper divisors (1).

999091 is an equidigital number, since it uses as much as digits as its factorization.

999091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6561, while the sum is 37.

The square root of 999091 is about 999.5453966679. The cubic root of 999091 is about 99.9696908145.

It can be divided in two parts, 99 and 9091, that multiplied together give a palindrome (900009).

The spelling of 999091 in words is "nine hundred ninety-nine thousand, ninety-one".