1986686461 has 2 divisors, whose sum is σ = 1986686462. Its totient is φ = 1986686460.

The previous prime is 1986686437. The next prime is 1986686489. The reversal of 1986686461 is 1646866891.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1652016025 + 334670436 = 40645^2 + 18294^2 .

It is a cyclic number.

It is not a de Polignac number, because 1986686461 - 2¹³ = 1986678269 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1986686761) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 993343230 + 993343231.

It is an arithmetic number, because the mean of its divisors is an integer number (993343231).

Almost surely, 2^1986686461 is an apocalyptic number.

It is an amenable number.

1986686461 is a deficient number, since it is larger than the sum of its proper divisors (1).

1986686461 is an equidigital number, since it uses as much as digits as its factorization.

1986686461 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2985984, while the sum is 55.

The square root of 1986686461 is about 44572.2611160798. The cubic root of 1986686461 is about 1257.1191554729.

The spelling of 1986686461 in words is "one billion, nine hundred eighty-six million, six hundred eighty-six thousand, four hundred sixty-one".