1317633661 has 2 divisors, whose sum is σ = 1317633662. Its totient is φ = 1317633660.

The previous prime is 1317633623. The next prime is 1317633727. The reversal of 1317633661 is 1663367131.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1010858436 + 306775225 = 31794^2 + 17515^2 .

It is a cyclic number.

It is not a de Polignac number, because 1317633661 - 2⁷ = 1317633533 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1317633661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1317633601) 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, 658816830 + 658816831.

It is an arithmetic number, because the mean of its divisors is an integer number (658816831).

Almost surely, 2^1317633661 is an apocalyptic number.

It is an amenable number.

1317633661 is a deficient number, since it is larger than the sum of its proper divisors (1).

1317633661 is an equidigital number, since it uses as much as digits as its factorization.

1317633661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 40824, while the sum is 37.

The square root of 1317633661 is about 36299.2239724212. The cubic root of 1317633661 is about 1096.3054178063.

It can be divided in two parts, 131763 and 3661, that added together give a square (135424 = 368²).

The spelling of 1317633661 in words is "one billion, three hundred seventeen million, six hundred thirty-three thousand, six hundred sixty-one".