1643591712 has 72 divisors (see below), whose sum is σ = 5018839056. Its totient is φ = 469596288.

The previous prime is 1643591711. The next prime is 1643591743. The reversal of 1643591712 is 2171953461.

It is not an unprimeable number, because it can be changed into a prime (1643591711) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 169998 + ... + 179405.

It is an arithmetic number, because the mean of its divisors is an integer number (69706098).

Almost surely, 2^1643591712 is an apocalyptic number.

1643591712 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1643591712 is an abundant number, since it is smaller than the sum of its proper divisors (3375247344).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1643591712 is a wasteful number, since it uses less digits than its factorization.

1643591712 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 349430 (or 349415 counting only the distinct ones).

The product of its digits is 45360, while the sum is 39.

The square root of 1643591712 is about 40541.2347123272. The cubic root of 1643591712 is about 1180.1339769356.

The spelling of 1643591712 in words is "one billion, six hundred forty-three million, five hundred ninety-one thousand, seven hundred twelve".