1209987657677 has 2 divisors, whose sum is σ = 1209987657678. Its totient is φ = 1209987657676.

The previous prime is 1209987657643. The next prime is 1209987657761. The reversal of 1209987657677 is 7767567899021.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1116095054116 + 93892603561 = 1056454^2 + 306419^2 .

It is a cyclic number.

It is not a de Polignac number, because 1209987657677 - 2⁴⁰ = 110476029901 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1209987657607) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 604993828838 + 604993828839.

It is an arithmetic number, because the mean of its divisors is an integer number (604993828839).

Almost surely, 2^{1209987657677} is an apocalyptic number.

It is an amenable number.

1209987657677 is a deficient number, since it is larger than the sum of its proper divisors (1).

1209987657677 is an equidigital number, since it uses as much as digits as its factorization.

1209987657677 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 560105280, while the sum is 74.

The spelling of 1209987657677 in words is "one trillion, two hundred nine billion, nine hundred eighty-seven million, six hundred fifty-seven thousand, six hundred seventy-seven".