4921668521 has 16 divisors (see below), whose sum is σ = 6497055360. Its totient is φ = 3609473280.

The previous prime is 4921668511. The next prime is 4921668527. The reversal of 4921668521 is 1258661294.

It is not a de Polignac number, because 4921668521 - 2¹⁰ = 4921667497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (4921668527) 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, 1878626 + ... + 1881243.

It is an arithmetic number, because the mean of its divisors is an integer number (406065960).

Almost surely, 2^4921668521 is an apocalyptic number.

It is an amenable number.

4921668521 is a deficient number, since it is larger than the sum of its proper divisors (1575386839).

4921668521 is a wasteful number, since it uses less digits than its factorization.

4921668521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3759904.

The product of its digits is 207360, while the sum is 44.

The square root of 4921668521 is about 70154.6044176717. The cubic root of 4921668521 is about 1700.9992419529. Note that the first 3 decimals are identical.

The spelling of 4921668521 in words is "four billion, nine hundred twenty-one million, six hundred sixty-eight thousand, five hundred twenty-one".