1316644561 has 4 divisors (see below), whose sum is σ = 1316840512. Its totient is φ = 1316448612.

The previous prime is 1316644541. The next prime is 1316644579. The reversal of 1316644561 is 1654466131.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1654466131 = 13441 ⋅123091.

It is a cyclic number.

It is not a de Polignac number, because 1316644561 - 2¹¹ = 1316642513 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1316644561.

It is not an unprimeable number, because it can be changed into a prime (1316644541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 87525 + ... + 101458.

It is an arithmetic number, because the mean of its divisors is an integer number (329210128).

Almost surely, 2^1316644561 is an apocalyptic number.

It is an amenable number.

1316644561 is a deficient number, since it is larger than the sum of its proper divisors (195951).

1316644561 is an equidigital number, since it uses as much as digits as its factorization.

1316644561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195950.

The product of its digits is 51840, while the sum is 37.

The square root of 1316644561 is about 36285.5971564476. The cubic root of 1316644561 is about 1096.0310301767.

The spelling of 1316644561 in words is "one billion, three hundred sixteen million, six hundred forty-four thousand, five hundred sixty-one".