1287429085 has 4 divisors (see below), whose sum is σ = 1544914908. Its totient is φ = 1029943264.

The previous prime is 1287429083. The next prime is 1287429119. The reversal of 1287429085 is 5809247821.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 208109476 + 1079319609 = 14426^2 + 32853^2 .

It is a cyclic number.

It is not a de Polignac number, because 1287429085 - 2¹ = 1287429083 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1287429083) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 128742904 + ... + 128742913.

It is an arithmetic number, because the mean of its divisors is an integer number (386228727).

Almost surely, 2^1287429085 is an apocalyptic number.

It is an amenable number.

1287429085 is a deficient number, since it is larger than the sum of its proper divisors (257485823).

1287429085 is an equidigital number, since it uses as much as digits as its factorization.

1287429085 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 257485822.

The product of its (nonzero) digits is 322560, while the sum is 46.

The square root of 1287429085 is about 35880.7620459767. The cubic root of 1287429085 is about 1087.8635831906.

The spelling of 1287429085 in words is "one billion, two hundred eighty-seven million, four hundred twenty-nine thousand, eighty-five".