2561603 has 8 divisors (see below), whose sum is σ = 2842560. Its totient is φ = 2288680.

The previous prime is 2561593. The next prime is 2561627. The reversal of 2561603 is 3061652.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2561603 - 2¹² = 2557507 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2561633) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1325 + ... + 2622.

It is an arithmetic number, because the mean of its divisors is an integer number (355320).

2^2561603 is an apocalyptic number.

2561603 is a deficient number, since it is larger than the sum of its proper divisors (280957).

2561603 is a wasteful number, since it uses less digits than its factorization.

2561603 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4017.

The product of its (nonzero) digits is 1080, while the sum is 23.

The square root of 2561603 is about 1600.5008591063. The cubic root of 2561603 is about 136.8266228124.

The spelling of 2561603 in words is "two million, five hundred sixty-one thousand, six hundred three".