75603551521 has 3 divisors (see below), whose sum is σ = 75603826483. Its totient is φ = 75603276560.

The previous prime is 75603551519. The next prime is 75603551531. The reversal of 75603551521 is 12515530657.

The square root of 75603551521 is 274961.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 461777121 + 75141774400 = 21489^2 + 274120^2 .

It is not a de Polignac number, because 75603551521 - 2¹ = 75603551519 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (75603551531) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 137481 + ... + 412441.

Almost surely, 2^75603551521 is an apocalyptic number.

75603551521 is the 274961-st square number.

75603551521 is the 137481-st centered octagonal number.

It is an amenable number.

75603551521 is a deficient number, since it is larger than the sum of its proper divisors (274962).

75603551521 is an frugal number, since it uses more digits than its factorization.

75603551521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 549922 (or 274961 counting only the distinct ones).

The product of its (nonzero) digits is 157500, while the sum is 40.

The spelling of 75603551521 in words is "seventy-five billion, six hundred three million, five hundred fifty-one thousand, five hundred twenty-one".