1287705393 has 24 divisors (see below), whose sum is σ = 2090192832. Its totient is φ = 757978848.

The previous prime is 1287705343. The next prime is 1287705401. The reversal of 1287705393 is 3935077821.

It is a happy number.

It is not a de Polignac number, because 1287705393 - 2⁶ = 1287705329 is a prime.

It is a super-2 number, since 2×1287705393² = 3316370358322568898, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1287705343) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 236571 + ... + 241952.

It is an arithmetic number, because the mean of its divisors is an integer number (87091368).

Almost surely, 2^1287705393 is an apocalyptic number.

1287705393 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

1287705393 is a deficient number, since it is larger than the sum of its proper divisors (802487439).

1287705393 is a wasteful number, since it uses less digits than its factorization.

1287705393 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 478565 (or 478562 counting only the distinct ones).

The product of its (nonzero) digits is 317520, while the sum is 45.

The square root of 1287705393 is about 35884.6122035616. The cubic root of 1287705393 is about 1087.9414033758.

The spelling of 1287705393 in words is "one billion, two hundred eighty-seven million, seven hundred five thousand, three hundred ninety-three".