1331552605 has 4 divisors (see below), whose sum is σ = 1597863132. Its totient is φ = 1065242080.

The previous prime is 1331552597. The next prime is 1331552627. The reversal of 1331552605 is 5062551331.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5062551331 = 12907 ⋅392233.

It can be written as a sum of positive squares in 2 ways, for example, as 828806521 + 502746084 = 28789^2 + 22422^2 .

It is not a de Polignac number, because 1331552605 - 2³ = 1331552597 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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, 133155256 + ... + 133155265.

It is an arithmetic number, because the mean of its divisors is an integer number (399465783).

Almost surely, 2^1331552605 is an apocalyptic number.

It is an amenable number.

1331552605 is a deficient number, since it is larger than the sum of its proper divisors (266310527).

1331552605 is an equidigital number, since it uses as much as digits as its factorization.

1331552605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 266310526.

The product of its (nonzero) digits is 13500, while the sum is 31.

The square root of 1331552605 is about 36490.4453932807. The cubic root of 1331552605 is about 1100.1522117192.

The spelling of 1331552605 in words is "one billion, three hundred thirty-one million, five hundred fifty-two thousand, six hundred five".