9865142081 has 2 divisors, whose sum is σ = 9865142082. Its totient is φ = 9865142080.

The previous prime is 9865142051. The next prime is 9865142123. The reversal of 9865142081 is 1802415689.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7758791056 + 2106351025 = 88084^2 + 45895^2 .

It is a cyclic number.

It is not a de Polignac number, because 9865142081 - 2⁶ = 9865142017 is a prime.

It is a super-2 number, since 2×9865142081² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (9865142051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4932571040 + 4932571041.

It is an arithmetic number, because the mean of its divisors is an integer number (4932571041).

Almost surely, 2^9865142081 is an apocalyptic number.

It is an amenable number.

9865142081 is a deficient number, since it is larger than the sum of its proper divisors (1).

9865142081 is an equidigital number, since it uses as much as digits as its factorization.

9865142081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 138240, while the sum is 44.

The square root of 9865142081 is about 99323.4216134342. The cubic root of 9865142081 is about 2144.7060727472.

The spelling of 9865142081 in words is "nine billion, eight hundred sixty-five million, one hundred forty-two thousand, eighty-one".