1605557413 has 4 divisors (see below), whose sum is σ = 1606016160. Its totient is φ = 1605098668.

The previous prime is 1605557377. The next prime is 1605557441. The reversal of 1605557413 is 3147555061.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1605557413 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 (1605552413) 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, 224083 + ... + 231136.

It is an arithmetic number, because the mean of its divisors is an integer number (401504040).

Almost surely, 2^1605557413 is an apocalyptic number.

It is an amenable number.

1605557413 is a deficient number, since it is larger than the sum of its proper divisors (458747).

1605557413 is an equidigital number, since it uses as much as digits as its factorization.

1605557413 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 458746.

The product of its (nonzero) digits is 63000, while the sum is 37.

The square root of 1605557413 is about 40069.4074450821. The cubic root of 1605557413 is about 1170.9596949754.

The spelling of 1605557413 in words is "one billion, six hundred five million, five hundred fifty-seven thousand, four hundred thirteen".