1605663256 has 32 divisors (see below), whose sum is σ = 3105190080. Its totient is φ = 777952000.

The previous prime is 1605663221. The next prime is 1605663263. The reversal of 1605663256 is 6523665061.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16836 + ... + 59116.

It is an arithmetic number, because the mean of its divisors is an integer number (97037190).

Almost surely, 2^1605663256 is an apocalyptic number.

It is an amenable number.

1605663256 is a deficient number, since it is larger than the sum of its proper divisors (1499526824).

1605663256 is a wasteful number, since it uses less digits than its factorization.

1605663256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42435 (or 42431 counting only the distinct ones).

The product of its (nonzero) digits is 194400, while the sum is 40.

The square root of 1605663256 is about 40070.7281690762. The cubic root of 1605663256 is about 1170.9854254294.

The spelling of 1605663256 in words is "one billion, six hundred five million, six hundred sixty-three thousand, two hundred fifty-six".