6648413621 has 2 divisors, whose sum is σ = 6648413622. Its totient is φ = 6648413620.

The previous prime is 6648413617. The next prime is 6648413641. The reversal of 6648413621 is 1263148466.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5247408721 + 1401004900 = 72439^2 + 37430^2 .

It is a cyclic number.

It is not a de Polignac number, because 6648413621 - 2² = 6648413617 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6648413641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3324206810 + 3324206811.

It is an arithmetic number, because the mean of its divisors is an integer number (3324206811).

Almost surely, 2^6648413621 is an apocalyptic number.

It is an amenable number.

6648413621 is a deficient number, since it is larger than the sum of its proper divisors (1).

6648413621 is an equidigital number, since it uses as much as digits as its factorization.

6648413621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 165888, while the sum is 41.

The square root of 6648413621 is about 81537.8048576242. The cubic root of 6648413621 is about 1880.3528103701.

The spelling of 6648413621 in words is "six billion, six hundred forty-eight million, four hundred thirteen thousand, six hundred twenty-one".