1661443204 has 24 divisors (see below), whose sum is σ = 2948702400. Its totient is φ = 818998944.

The previous prime is 1661443193. The next prime is 1661443211. The reversal of 1661443204 is 4023441661.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 162022 + ... + 171970.

It is an arithmetic number, because the mean of its divisors is an integer number (122862600).

Almost surely, 2^1661443204 is an apocalyptic number.

It is an amenable number.

1661443204 is a deficient number, since it is larger than the sum of its proper divisors (1287259196).

1661443204 is a wasteful number, since it uses less digits than its factorization.

1661443204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10539 (or 10537 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 31.

The square root of 1661443204 is about 40760.8047516238. The cubic root of 1661443204 is about 1184.3911853029.

Adding to 1661443204 its reverse (4023441661), we get a palindrome (5684884865).

The spelling of 1661443204 in words is "one billion, six hundred sixty-one million, four hundred forty-three thousand, two hundred four".