1605139 has 4 divisors (see below), whose sum is σ = 1689640. Its totient is φ = 1520640.

The previous prime is 1605127. The next prime is 1605151. The reversal of 1605139 is 9315061.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (1605127) and next prime (1605151).

It is a cyclic number.

It is not a de Polignac number, because 1605139 - 2¹⁹ = 1080851 is a prime.

It is a Duffinian number.

1605139 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1605169) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42222 + ... + 42259.

It is an arithmetic number, because the mean of its divisors is an integer number (422410).

2^1605139 is an apocalyptic number.

1605139 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

1605139 is a deficient number, since it is larger than the sum of its proper divisors (84501).

1605139 is an equidigital number, since it uses as much as digits as its factorization.

1605139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84500.

The product of its (nonzero) digits is 810, while the sum is 25.

The square root of 1605139 is about 1266.9408036684. The cubic root of 1605139 is about 117.0857967621.

The spelling of 1605139 in words is "one million, six hundred five thousand, one hundred thirty-nine".