521561603 has 8 divisors (see below), whose sum is σ = 527090448. Its totient is φ = 516057984.

The previous prime is 521561597. The next prime is 521561641. The reversal of 521561603 is 306165125.

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 521561603 - 2⁴ = 521561587 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (521561653) 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, 36800 + ... + 48962.

It is an arithmetic number, because the mean of its divisors is an integer number (65886306).

Almost surely, 2^521561603 is an apocalyptic number.

521561603 is a deficient number, since it is larger than the sum of its proper divisors (5528845).

521561603 is a wasteful number, since it uses less digits than its factorization.

521561603 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12613.

The product of its (nonzero) digits is 5400, while the sum is 29.

The square root of 521561603 is about 22837.7232446669. The cubic root of 521561603 is about 804.9493187233.

The spelling of 521561603 in words is "five hundred twenty-one million, five hundred sixty-one thousand, six hundred three".