5515641821 has 2 divisors, whose sum is σ = 5515641822. Its totient is φ = 5515641820.

The previous prime is 5515641797. The next prime is 5515641851. The reversal of 5515641821 is 1281465155.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5356629721 + 159012100 = 73189^2 + 12610^2 .

It is a cyclic number.

It is not a de Polignac number, because 5515641821 - 2¹⁰ = 5515640797 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (5515641851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2757820910 + 2757820911.

It is an arithmetic number, because the mean of its divisors is an integer number (2757820911).

Almost surely, 2^5515641821 is an apocalyptic number.

It is an amenable number.

5515641821 is a deficient number, since it is larger than the sum of its proper divisors (1).

5515641821 is an equidigital number, since it uses as much as digits as its factorization.

5515641821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 48000, while the sum is 38.

The square root of 5515641821 is about 74267.3671338900. The cubic root of 5515641821 is about 1766.8459497934.

The spelling of 5515641821 in words is "five billion, five hundred fifteen million, six hundred forty-one thousand, eight hundred twenty-one".