1280115643 has 8 divisors (see below), whose sum is σ = 1321988096. Its totient is φ = 1238279400.

The previous prime is 1280115631. The next prime is 1280115647. The reversal of 1280115643 is 3465110821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1280115643 - 2⁵ = 1280115611 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1280115647) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 75478 + ... + 90868.

It is an arithmetic number, because the mean of its divisors is an integer number (165248512).

Almost surely, 2^1280115643 is an apocalyptic number.

1280115643 is a deficient number, since it is larger than the sum of its proper divisors (41872453).

1280115643 is a wasteful number, since it uses less digits than its factorization.

1280115643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18105.

The product of its (nonzero) digits is 5760, while the sum is 31.

The square root of 1280115643 is about 35778.7037635519. The cubic root of 1280115643 is about 1085.7997439238.

The spelling of 1280115643 in words is "one billion, two hundred eighty million, one hundred fifteen thousand, six hundred forty-three".