2001521553 has 16 divisors (see below), whose sum is σ = 2687440896. Its totient is φ = 1324992080.

The previous prime is 2001521527. The next prime is 2001521581. The reversal of 2001521553 is 3551251002.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 2001521553 - 2⁸ = 2001521297 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2001521593) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 785800 + ... + 788342.

It is an arithmetic number, because the mean of its divisors is an integer number (167965056).

Almost surely, 2^2001521553 is an apocalyptic number.

It is an amenable number.

2001521553 is a deficient number, since it is larger than the sum of its proper divisors (685919343).

2001521553 is a wasteful number, since it uses less digits than its factorization.

2001521553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4284.

The product of its (nonzero) digits is 1500, while the sum is 24.

The square root of 2001521553 is about 44738.3677954393. The cubic root of 2001521553 is about 1260.2404750137.

Adding to 2001521553 its reverse (3551251002), we get a palindrome (5552772555).

The spelling of 2001521553 in words is "two billion, one million, five hundred twenty-one thousand, five hundred fifty-three".