1605556223 has 4 divisors (see below), whose sum is σ = 1606253880. Its totient is φ = 1604858568.

The previous prime is 1605556217. The next prime is 1605556243. The reversal of 1605556223 is 3226555061.

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

It is a cyclic number.

It is not a de Polignac number, because 1605556223 - 2⁶ = 1605556159 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 (1605556243) 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, 345365 + ... + 349982.

It is an arithmetic number, because the mean of its divisors is an integer number (401563470).

Almost surely, 2^1605556223 is an apocalyptic number.

1605556223 is a deficient number, since it is larger than the sum of its proper divisors (697657).

1605556223 is an equidigital number, since it uses as much as digits as its factorization.

1605556223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 697656.

The product of its (nonzero) digits is 54000, while the sum is 35.

The square root of 1605556223 is about 40069.3925958455. The cubic root of 1605556223 is about 1170.9594056797.

The spelling of 1605556223 in words is "one billion, six hundred five million, five hundred fifty-six thousand, two hundred twenty-three".