1209676861 has 2 divisors, whose sum is σ = 1209676862. Its totient is φ = 1209676860.

The previous prime is 1209676847. The next prime is 1209676873. The reversal of 1209676861 is 1686769021.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1017992836 + 191684025 = 31906^2 + 13845^2 .

It is a cyclic number.

It is not a de Polignac number, because 1209676861 - 2⁷ = 1209676733 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1209676841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 604838430 + 604838431.

It is an arithmetic number, because the mean of its divisors is an integer number (604838431).

Almost surely, 2^1209676861 is an apocalyptic number.

It is an amenable number.

1209676861 is a deficient number, since it is larger than the sum of its proper divisors (1).

1209676861 is an equidigital number, since it uses as much as digits as its factorization.

1209676861 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 217728, while the sum is 46.

The square root of 1209676861 is about 34780.4091551551. The cubic root of 1209676861 is about 1065.5073694668.

The spelling of 1209676861 in words is "one billion, two hundred nine million, six hundred seventy-six thousand, eight hundred sixty-one".