1981768 has 32 divisors (see below), whose sum is σ = 3928320. Its totient is φ = 936000.

The previous prime is 1981753. The next prime is 1981787. The reversal of 1981768 is 8671891.

It is a self number, because there is not a number n which added to its sum of digits gives 1981768.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15063 + ... + 15193.

It is an arithmetic number, because the mean of its divisors is an integer number (122760).

2^1981768 is an apocalyptic number.

It is an amenable number.

1981768 is a deficient number, since it is larger than the sum of its proper divisors (1946552).

1981768 is a wasteful number, since it uses less digits than its factorization.

1981768 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 229 (or 225 counting only the distinct ones).

The product of its digits is 24192, while the sum is 40.

The square root of 1981768 is about 1407.7528192122. The cubic root of 1981768 is about 125.6080877046.

The spelling of 1981768 in words is "one million, nine hundred eighty-one thousand, seven hundred sixty-eight".