9787661801 has 2 divisors, whose sum is σ = 9787661802. Its totient is φ = 9787661800.

The previous prime is 9787661693. The next prime is 9787661813. The reversal of 9787661801 is 1081667879.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6072149776 + 3715512025 = 77924^2 + 60955^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9787661801 is a prime.

It is not a weakly prime, because it can be changed into another prime (9787663801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4893830900 + 4893830901.

It is an arithmetic number, because the mean of its divisors is an integer number (4893830901).

Almost surely, 2^9787661801 is an apocalyptic number.

It is an amenable number.

9787661801 is a deficient number, since it is larger than the sum of its proper divisors (1).

9787661801 is an equidigital number, since it uses as much as digits as its factorization.

9787661801 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1016064, while the sum is 53.

The square root of 9787661801 is about 98932.6124238110. The cubic root of 9787661801 is about 2139.0765078879.

The spelling of 9787661801 in words is "nine billion, seven hundred eighty-seven million, six hundred sixty-one thousand, eight hundred one".