1316609981 has 2 divisors, whose sum is σ = 1316609982. Its totient is φ = 1316609980.

The previous prime is 1316609929. The next prime is 1316610017. The reversal of 1316609981 is 1899066131.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 929701081 + 386908900 = 30491^2 + 19670^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1316609981 is a prime.

It is a super-2 number, since 2×1316609981² = 3466923684137640722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1316609881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 658304990 + 658304991.

It is an arithmetic number, because the mean of its divisors is an integer number (658304991).

Almost surely, 2^1316609981 is an apocalyptic number.

It is an amenable number.

1316609981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1316609981 is an equidigital number, since it uses as much as digits as its factorization.

1316609981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 69984, while the sum is 44.

The square root of 1316609981 is about 36285.1206557178. The cubic root of 1316609981 is about 1096.0214348042.

The spelling of 1316609981 in words is "one billion, three hundred sixteen million, six hundred nine thousand, nine hundred eighty-one".