1820728280 has 96 divisors (see below), whose sum is σ = 4777302240. Its totient is φ = 622702080.

The previous prime is 1820728279. The next prime is 1820728321. The reversal of 1820728280 is 828270281.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1020269 + ... + 1022051.

It is an arithmetic number, because the mean of its divisors is an integer number (49763565).

Almost surely, 2^1820728280 is an apocalyptic number.

1820728280 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 1820728280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2388651120).

1820728280 is an abundant number, since it is smaller than the sum of its proper divisors (2956573960).

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

1820728280 is a wasteful number, since it uses less digits than its factorization.

1820728280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2329 (or 2318 counting only the distinct ones).

The product of its (nonzero) digits is 28672, while the sum is 38.

The square root of 1820728280 is about 42669.9927349420. The cubic root of 1820728280 is about 1221.0919811946.

The spelling of 1820728280 in words is "one billion, eight hundred twenty million, seven hundred twenty-eight thousand, two hundred eighty".