1605165555 has 32 divisors (see below), whose sum is σ = 2936669184. Its totient is φ = 733412736.

The previous prime is 1605165553. The next prime is 1605165557. The reversal of 1605165555 is 5555615061.

It is an interprime number because it is at equal distance from previous prime (1605165553) and next prime (1605165557).

It is not a de Polignac number, because 1605165555 - 2¹ = 1605165553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1605165553) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 368802 + ... + 373128.

It is an arithmetic number, because the mean of its divisors is an integer number (91770912).

Almost surely, 2^1605165555 is an apocalyptic number.

1605165555 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1605165555 is a deficient number, since it is larger than the sum of its proper divisors (1331503629).

1605165555 is a wasteful number, since it uses less digits than its factorization.

1605165555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7875.

The product of its (nonzero) digits is 112500, while the sum is 39.

The square root of 1605165555 is about 40064.5174063035. The cubic root of 1605165555 is about 1170.8644243744.

The spelling of 1605165555 in words is "one billion, six hundred five million, one hundred sixty-five thousand, five hundred fifty-five".