6690941281 has 2 divisors, whose sum is σ = 6690941282. Its totient is φ = 6690941280.

The previous prime is 6690941273. The next prime is 6690941297. The reversal of 6690941281 is 1821490966.

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., 6137939025 + 553002256 = 78345^2 + 23516^2 .

It is a cyclic number.

It is not a de Polignac number, because 6690941281 - 2³ = 6690941273 is a prime.

It is a super-2 number, since 2×6690941281² = 89537390451579841922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (6690941981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3345470640 + 3345470641.

It is an arithmetic number, because the mean of its divisors is an integer number (3345470641).

Almost surely, 2^6690941281 is an apocalyptic number.

It is an amenable number.

6690941281 is a deficient number, since it is larger than the sum of its proper divisors (1).

6690941281 is an equidigital number, since it uses as much as digits as its factorization.

6690941281 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 186624, while the sum is 46.

The square root of 6690941281 is about 81798.1740688629. The cubic root of 6690941281 is about 1884.3536194647.

The spelling of 6690941281 in words is "six billion, six hundred ninety million, nine hundred forty-one thousand, two hundred eighty-one".