1289491513 has 4 divisors (see below), whose sum is σ = 1289900068. Its totient is φ = 1289082960.

The previous prime is 1289491501. The next prime is 1289491523. The reversal of 1289491513 is 3151949821.

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 286692624 + 1002798889 = 16932^2 + 31667^2 .

It is a cyclic number.

It is not a de Polignac number, because 1289491513 - 2¹⁷ = 1289360441 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1289491513.

It is not an unprimeable number, because it can be changed into a prime (1289491523) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 199506 + ... + 205867.

It is an arithmetic number, because the mean of its divisors is an integer number (322475017).

Almost surely, 2^1289491513 is an apocalyptic number.

It is an amenable number.

1289491513 is a deficient number, since it is larger than the sum of its proper divisors (408555).

1289491513 is an equidigital number, since it uses as much as digits as its factorization.

1289491513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 408554.

The product of its digits is 77760, while the sum is 43.

The square root of 1289491513 is about 35909.4905700429. The cubic root of 1289491513 is about 1088.4441830131. Note that the first 3 decimals are identical.

The spelling of 1289491513 in words is "one billion, two hundred eighty-nine million, four hundred ninety-one thousand, five hundred thirteen".