2781198728 has 64 divisors (see below), whose sum is σ = 6711275520. Its totient is φ = 1048622400.

The previous prime is 2781198661. The next prime is 2781198731. The reversal of 2781198728 is 8278911872.

It is a self number, because there is not a number n which added to its sum of digits gives 2781198728.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 53726 + ... + 91917.

It is an arithmetic number, because the mean of its divisors is an integer number (104863680).

Almost surely, 2^2781198728 is an apocalyptic number.

2781198728 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

2781198728 is an abundant number, since it is smaller than the sum of its proper divisors (3930076792).

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

2781198728 is a wasteful number, since it uses less digits than its factorization.

2781198728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145698 (or 145694 counting only the distinct ones).

The product of its digits is 903168, while the sum is 53.

The square root of 2781198728 is about 52737.0716669024. The cubic root of 2781198728 is about 1406.2979403364.

The spelling of 2781198728 in words is "two billion, seven hundred eighty-one million, one hundred ninety-eight thousand, seven hundred twenty-eight".