1931978880 has 192 divisors, whose sum is σ = 7184824920. Its totient is φ = 475545600.

The previous prime is 1931978837. The next prime is 1931978899. The reversal of 1931978880 is 888791391.

It can be written as a sum of positive squares in 4 ways, for example, as 1226120256 + 705858624 = 35016^2 + 26568^2 .

It is a tau number, because it is divible by the number of its divisors (192).

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 23 ways as a sum of consecutive naturals, for example, 61980 + ... + 87780.

Almost surely, 2^1931978880 is an apocalyptic number.

1931978880 is a gapful number since it is divisible by the number (10) 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 1931978880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3592412460).

1931978880 is an abundant number, since it is smaller than the sum of its proper divisors (5252846040).

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

1931978880 is a wasteful number, since it uses less digits than its factorization.

1931978880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25839 (or 25824 counting only the distinct ones).

The product of its (nonzero) digits is 870912, while the sum is 54.

The square root of 1931978880 is about 43954.2817026965. The cubic root of 1931978880 is about 1245.4724485549.

The spelling of 1931978880 in words is "one billion, nine hundred thirty-one million, nine hundred seventy-eight thousand, eight hundred eighty".