6553523821 has 4 divisors (see below), whose sum is σ = 7057641052. Its totient is φ = 6049406592.

The previous prime is 6553523761. The next prime is 6553523839. The reversal of 6553523821 is 1283253556.

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

It can be written as a sum of positive squares in 2 ways, for example, as 389075625 + 6164448196 = 19725^2 + 78514^2 .

It is a cyclic number.

It is not a de Polignac number, because 6553523821 - 2¹¹ = 6553521773 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 (6553523891) 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, 252058596 + ... + 252058621.

It is an arithmetic number, because the mean of its divisors is an integer number (1764410263).

Almost surely, 2^6553523821 is an apocalyptic number.

It is an amenable number.

6553523821 is a deficient number, since it is larger than the sum of its proper divisors (504117231).

6553523821 is a wasteful number, since it uses less digits than its factorization.

6553523821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 504117230.

The product of its digits is 216000, while the sum is 40.

The square root of 6553523821 is about 80953.8375927911. The cubic root of 6553523821 is about 1871.3641014924.

The spelling of 6553523821 in words is "six billion, five hundred fifty-three million, five hundred twenty-three thousand, eight hundred twenty-one".