8404201681 has 2 divisors, whose sum is σ = 8404201682. Its totient is φ = 8404201680.

The previous prime is 8404201601. The next prime is 8404201717. The reversal of 8404201681 is 1861024048.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7874787600 + 529414081 = 88740^2 + 23009^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8404201681 is a prime.

It is a super-2 number, since 2×8404201681² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (8404201601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4202100840 + 4202100841.

It is an arithmetic number, because the mean of its divisors is an integer number (4202100841).

Almost surely, 2^8404201681 is an apocalyptic number.

It is an amenable number.

8404201681 is a deficient number, since it is larger than the sum of its proper divisors (1).

8404201681 is an equidigital number, since it uses as much as digits as its factorization.

8404201681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12288, while the sum is 34.

The square root of 8404201681 is about 91674.4330825122. The cubic root of 8404201681 is about 2033.1315915195.

The spelling of 8404201681 in words is "eight billion, four hundred four million, two hundred one thousand, six hundred eighty-one".