1681844544 has 84 divisors (see below), whose sum is σ = 5104304244. Its totient is φ = 527634432.

The previous prime is 1681844513. The next prime is 1681844551. The reversal of 1681844544 is 4454481861.

1681844544 is a `hidden beast` number, since 1 + 68 + 1 + 8 + 44 + 544 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1543546944 + 138297600 = 39288^2 + 11760^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1681844544.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 76087 + ... + 95670.

Almost surely, 2^1681844544 is an apocalyptic number.

It is an amenable number.

1681844544 is an abundant number, since it is smaller than the sum of its proper divisors (3422459700).

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

1681844544 is a wasteful number, since it uses less digits than its factorization.

1681844544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171792 (or 171779 counting only the distinct ones).

The product of its digits is 491520, while the sum is 45.

The square root of 1681844544 is about 41010.2980237891. The cubic root of 1681844544 is about 1189.2193038649.

The spelling of 1681844544 in words is "one billion, six hundred eighty-one million, eight hundred forty-four thousand, five hundred forty-four".