1981795776 has 112 divisors (see below), whose sum is σ = 5559552000. Its totient is φ = 621941760.

The previous prime is 1981795691. The next prime is 1981795787. The reversal of 1981795776 is 6775971891.

Its product of digits (6667920) is a multiple of the sum of its prime divisors (9072).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 215725 + ... + 224723.

Almost surely, 2^1981795776 is an apocalyptic number.

1981795776 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 1981795776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2779776000).

1981795776 is an abundant number, since it is smaller than the sum of its proper divisors (3577756224).

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

1981795776 is a wasteful number, since it uses less digits than its factorization.

1981795776 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9082 (or 9072 counting only the distinct ones).

The product of its digits is 6667920, while the sum is 60.

The square root of 1981795776 is about 44517.3648815830. The cubic root of 1981795776 is about 1256.0867453307.

The spelling of 1981795776 in words is "one billion, nine hundred eighty-one million, seven hundred ninety-five thousand, seven hundred seventy-six".