1661881268 has 12 divisors (see below), whose sum is σ = 2909007360. Its totient is φ = 830736312.

The previous prime is 1661881241. The next prime is 1661881271. The reversal of 1661881268 is 8621881661.

It is a congruent number.

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, 31988 + ... + 65931.

It is an arithmetic number, because the mean of its divisors is an integer number (242417280).

Almost surely, 2^1661881268 is an apocalyptic number.

It is an amenable number.

1661881268 is a deficient number, since it is larger than the sum of its proper divisors (1247126092).

1661881268 is a wasteful number, since it uses less digits than its factorization.

1661881268 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102166 (or 102164 counting only the distinct ones).

The product of its digits is 221184, while the sum is 47.

The square root of 1661881268 is about 40766.1779910749. The cubic root of 1661881268 is about 1184.4952702225.

The spelling of 1661881268 in words is "one billion, six hundred sixty-one million, eight hundred eighty-one thousand, two hundred sixty-eight".