1281040723 has 2 divisors, whose sum is σ = 1281040724. Its totient is φ = 1281040722.

The previous prime is 1281040721. The next prime is 1281040727. The reversal of 1281040723 is 3270401821.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1281040723 - 2¹ = 1281040721 is a prime.

Together with 1281040721, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 1281040691 and 1281040700.

It is not a weakly prime, because it can be changed into another prime (1281040721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 640520361 + 640520362.

It is an arithmetic number, because the mean of its divisors is an integer number (640520362).

Almost surely, 2^1281040723 is an apocalyptic number.

1281040723 is a deficient number, since it is larger than the sum of its proper divisors (1).

1281040723 is an equidigital number, since it uses as much as digits as its factorization.

1281040723 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2688, while the sum is 28.

The square root of 1281040723 is about 35791.6292308691. The cubic root of 1281040723 is about 1086.0612332595.

The spelling of 1281040723 in words is "one billion, two hundred eighty-one million, forty thousand, seven hundred twenty-three".