2809531840 has 28 divisors (see below), whose sum is σ = 6690198456. Its totient is φ = 1123812608.

The previous prime is 2809531817. The next prime is 2809531853. The reversal of 2809531840 is 481359082.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 2809531793 and 2809531802.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4389574 + ... + 4390213.

Almost surely, 2^2809531840 is an apocalyptic number.

2809531840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2809531840 is an abundant number, since it is smaller than the sum of its proper divisors (3880666616).

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

2809531840 is an equidigital number, since it uses as much as digits as its factorization.

2809531840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8779804 (or 8779794 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 40.

The square root of 2809531840 is about 53005.0171210236. The cubic root of 2809531840 is about 1411.0573093386.

The spelling of 2809531840 in words is "two billion, eight hundred nine million, five hundred thirty-one thousand, eight hundred forty".