661700381686163 has 2 divisors, whose sum is σ = 661700381686164. Its totient is φ = 661700381686162.

The previous prime is 661700381686121. The next prime is 661700381686277. The reversal of 661700381686163 is 361686183007166.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 661700381686163 - 2¹⁰ = 661700381685139 is a prime.

It is a super-2 number, since 2×661700381686163² (a number of 30 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 661700381686096 and 661700381686105.

It is not a weakly prime, because it can be changed into another prime (661700381616163) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330850190843081 + 330850190843082.

It is an arithmetic number, because the mean of its divisors is an integer number (330850190843082).

Almost surely, 2^{661700381686163} is an apocalyptic number.

661700381686163 is a deficient number, since it is larger than the sum of its proper divisors (1).

661700381686163 is an equidigital number, since it uses as much as digits as its factorization.

661700381686163 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 31352832, while the sum is 62.

The spelling of 661700381686163 in words is "six hundred sixty-one trillion, seven hundred billion, three hundred eighty-one million, six hundred eighty-six thousand, one hundred sixty-three".