1290981385 has 12 divisors (see below), whose sum is σ = 1557315468. Its totient is φ = 1027388096.

The previous prime is 1290981347. The next prime is 1290981403. The reversal of 1290981385 is 5831890921.

It can be written as a sum of positive squares in 6 ways, for example, as 83557881 + 1207423504 = 9141^2 + 34748^2 .

It is not a de Polignac number, because 1290981385 - 2²⁵ = 1257426953 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 190719 + ... + 197371.

It is an arithmetic number, because the mean of its divisors is an integer number (129776289).

Almost surely, 2^1290981385 is an apocalyptic number.

It is an amenable number.

1290981385 is a deficient number, since it is larger than the sum of its proper divisors (266334083).

1290981385 is an frugal number, since it uses more digits than its factorization.

1290981385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7052 (or 6855 counting only the distinct ones).

The product of its (nonzero) digits is 155520, while the sum is 46.

The square root of 1290981385 is about 35930.2294036651. The cubic root of 1290981385 is about 1088.8632159808.

The spelling of 1290981385 in words is "one billion, two hundred ninety million, nine hundred eighty-one thousand, three hundred eighty-five".