1643954 has 16 divisors (see below), whose sum is σ = 2707992. Its totient is φ = 743808.

The previous prime is 1643893. The next prime is 1643959. The reversal of 1643954 is 4593461.

It can be written as a sum of positive squares in 4 ways, for example, as 1311025 + 332929 = 1145^2 + 577^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1643954.

It is not an unprimeable number, because it can be changed into a prime (1643959) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 782 + ... + 1974.

2^1643954 is an apocalyptic number.

1643954 is a deficient number, since it is larger than the sum of its proper divisors (1064038).

1643954 is a wasteful number, since it uses less digits than its factorization.

1643954 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1261.

The product of its digits is 12960, while the sum is 32.

The square root of 1643954 is about 1282.1676957403. The cubic root of 1643954 is about 118.0220680741.

The spelling of 1643954 in words is "one million, six hundred forty-three thousand, nine hundred fifty-four".