1605622161 has 16 divisors (see below), whose sum is σ = 2515101120. Its totient is φ = 898249920.

The previous prime is 1605622129. The next prime is 1605622163. The reversal of 1605622161 is 1612265061.

It is not a de Polignac number, because 1605622161 - 2⁵ = 1605622129 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1605622163) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1870926 + ... + 1871783.

It is an arithmetic number, because the mean of its divisors is an integer number (157193820).

Almost surely, 2^1605622161 is an apocalyptic number.

1605622161 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1605622161 is a deficient number, since it is larger than the sum of its proper divisors (909478959).

1605622161 is a wasteful number, since it uses less digits than its factorization.

1605622161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3742736.

The product of its (nonzero) digits is 4320, while the sum is 30.

The square root of 1605622161 is about 40070.2153849964. The cubic root of 1605622161 is about 1170.9754353612.

The spelling of 1605622161 in words is "one billion, six hundred five million, six hundred twenty-two thousand, one hundred sixty-one".