1643565316 has 24 divisors (see below), whose sum is σ = 2971987200. Its totient is φ = 794479200.

The previous prime is 1643565283. The next prime is 1643565353. The reversal of 1643565316 is 6135653461.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 129210 + ... + 141358.

It is an arithmetic number, because the mean of its divisors is an integer number (123832800).

Almost surely, 2^1643565316 is an apocalyptic number.

It is an amenable number.

1643565316 is a deficient number, since it is larger than the sum of its proper divisors (1328421884).

1643565316 is a wasteful number, since it uses less digits than its factorization.

1643565316 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13275 (or 13273 counting only the distinct ones).

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

The square root of 1643565316 is about 40540.9091659277. The cubic root of 1643565316 is about 1180.1276592710.

The spelling of 1643565316 in words is "one billion, six hundred forty-three million, five hundred sixty-five thousand, three hundred sixteen".