1391669633261 has 2 divisors, whose sum is σ = 1391669633262. Its totient is φ = 1391669633260.

The previous prime is 1391669633239. The next prime is 1391669633273. The reversal of 1391669633261 is 1623369661931.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 887328204361 + 504341428900 = 941981^2 + 710170^2 .

It is a cyclic number.

It is not a de Polignac number, because 1391669633261 - 2¹⁰ = 1391669632237 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1391669633197 and 1391669633206.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1391669633161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 695834816630 + 695834816631.

It is an arithmetic number, because the mean of its divisors is an integer number (695834816631).

Almost surely, 2^{1391669633261} is an apocalyptic number.

It is an amenable number.

1391669633261 is a deficient number, since it is larger than the sum of its proper divisors (1).

1391669633261 is an equidigital number, since it uses as much as digits as its factorization.

1391669633261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5668704, while the sum is 56.

The spelling of 1391669633261 in words is "one trillion, three hundred ninety-one billion, six hundred sixty-nine million, six hundred thirty-three thousand, two hundred sixty-one".