6735221921 has 2 divisors, whose sum is σ = 6735221922. Its totient is φ = 6735221920.

The previous prime is 6735221917. The next prime is 6735221929. The reversal of 6735221921 is 1291225376.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5784363025 + 950858896 = 76055^2 + 30836^2 .

It is a cyclic number.

It is not a de Polignac number, because 6735221921 - 2² = 6735221917 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (6735221929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3367610960 + 3367610961.

It is an arithmetic number, because the mean of its divisors is an integer number (3367610961).

Almost surely, 2^6735221921 is an apocalyptic number.

It is an amenable number.

6735221921 is a deficient number, since it is larger than the sum of its proper divisors (1).

6735221921 is an equidigital number, since it uses as much as digits as its factorization.

6735221921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 45360, while the sum is 38.

The square root of 6735221921 is about 82068.3978215732. The cubic root of 6735221921 is about 1888.5013661519.

The spelling of 6735221921 in words is "six billion, seven hundred thirty-five million, two hundred twenty-one thousand, nine hundred twenty-one".