7280243865 has 12 divisors (see below), whose sum is σ = 12619089444. Its totient is φ = 3882796704.

The previous prime is 7280243857. The next prime is 7280243869. The reversal of 7280243865 is 5683420827.

It can be written as a sum of positive squares in 2 ways, for example, as 773562969 + 6506680896 = 27813^2 + 80664^2 .

It is not a de Polignac number, because 7280243865 - 2³ = 7280243857 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 161783197 = 7280243865 / (7 + 2 + 8 + 0 + 2 + 4 + 3 + 8 + 6 + 5).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 7280243865.

It is not an unprimeable number, because it can be changed into a prime (7280243869) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 80891554 + ... + 80891643.

It is an arithmetic number, because the mean of its divisors is an integer number (1051590787).

Almost surely, 2^7280243865 is an apocalyptic number.

It is an amenable number.

7280243865 is a deficient number, since it is larger than the sum of its proper divisors (5338845579).

7280243865 is a wasteful number, since it uses less digits than its factorization.

7280243865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161783208 (or 161783205 counting only the distinct ones).

The product of its (nonzero) digits is 645120, while the sum is 45.

The square root of 7280243865 is about 85324.3450897808. The cubic root of 7280243865 is about 1938.1258572777.

The spelling of 7280243865 in words is "seven billion, two hundred eighty million, two hundred forty-three thousand, eight hundred sixty-five".