6681089521 has 2 divisors, whose sum is σ = 6681089522. Its totient is φ = 6681089520.

The previous prime is 6681089507. The next prime is 6681089561. The reversal of 6681089521 is 1259801866.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5892097600 + 788991921 = 76760^2 + 28089^2 .

It is a cyclic number.

It is not a de Polignac number, because 6681089521 - 2⁵ = 6681089489 is a prime.

It is not a weakly prime, because it can be changed into another prime (6681089561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3340544760 + 3340544761.

It is an arithmetic number, because the mean of its divisors is an integer number (3340544761).

Almost surely, 2^6681089521 is an apocalyptic number.

It is an amenable number.

6681089521 is a deficient number, since it is larger than the sum of its proper divisors (1).

6681089521 is an equidigital number, since it uses as much as digits as its factorization.

6681089521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 207360, while the sum is 46.

The square root of 6681089521 is about 81737.9319594030. The cubic root of 6681089521 is about 1883.4283227279.

The spelling of 6681089521 in words is "six billion, six hundred eighty-one million, eighty-nine thousand, five hundred twenty-one".