1981944576 has 108 divisors (see below), whose sum is σ = 5898984000. Its totient is φ = 639313920.

The previous prime is 1981944557. The next prime is 1981944581. The reversal of 1981944576 is 6754491891.

1981944576 is a `hidden beast` number, since 19 + 8 + 19 + 44 + 576 = 666.

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, 57550 + ... + 85298.

Almost surely, 2^1981944576 is an apocalyptic number.

1981944576 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1981944576, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2949492000).

1981944576 is an abundant number, since it is smaller than the sum of its proper divisors (3917039424).

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

1981944576 is a wasteful number, since it uses less digits than its factorization.

1981944576 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27802 (or 27785 counting only the distinct ones).

The product of its digits is 2177280, while the sum is 54.

The square root of 1981944576 is about 44519.0361081639. The cubic root of 1981944576 is about 1256.1181816392.

The spelling of 1981944576 in words is "one billion, nine hundred eighty-one million, nine hundred forty-four thousand, five hundred seventy-six".