1645334816 has 24 divisors (see below), whose sum is σ = 3246308604. Its totient is φ = 820875520.

The previous prime is 1645334777. The next prime is 1645334837. The reversal of 1645334816 is 6184335461.

It can be written as a sum of positive squares in 2 ways, for example, as 1383542416 + 261792400 = 37196^2 + 16180^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41015 + ... + 70518.

Almost surely, 2^1645334816 is an apocalyptic number.

1645334816 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1645334816 is a deficient number, since it is larger than the sum of its proper divisors (1600973788).

1645334816 is a wasteful number, since it uses less digits than its factorization.

1645334816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112004 (or 111996 counting only the distinct ones).

The product of its digits is 207360, while the sum is 41.

The square root of 1645334816 is about 40562.7269300278. The cubic root of 1645334816 is about 1180.5510248464.

The spelling of 1645334816 in words is "one billion, six hundred forty-five million, three hundred thirty-four thousand, eight hundred sixteen".