9861505481 has 2 divisors, whose sum is σ = 9861505482. Its totient is φ = 9861505480.

The previous prime is 9861505441. The next prime is 9861505517. The reversal of 9861505481 is 1845051689.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9533569600 + 327935881 = 97640^2 + 18109^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9861505481 is a prime.

It is a super-2 number, since 2×9861505481² (a number of 21 digits) contains 22 as substring.

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 (9861505421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4930752740 + 4930752741.

It is an arithmetic number, because the mean of its divisors is an integer number (4930752741).

Almost surely, 2^9861505481 is an apocalyptic number.

It is an amenable number.

9861505481 is a deficient number, since it is larger than the sum of its proper divisors (1).

9861505481 is an equidigital number, since it uses as much as digits as its factorization.

9861505481 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 345600, while the sum is 47.

The square root of 9861505481 is about 99305.1130657430. The cubic root of 9861505481 is about 2144.4425051064.

The spelling of 9861505481 in words is "nine billion, eight hundred sixty-one million, five hundred five thousand, four hundred eighty-one".