1383839981 has 2 divisors, whose sum is σ = 1383839982. Its totient is φ = 1383839980.

The previous prime is 1383839957. The next prime is 1383840023. The reversal of 1383839981 is 1899383831.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1208674756 + 175165225 = 34766^2 + 13235^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1383839981 is a prime.

It is a super-2 number, since 2×1383839981² = 3830026186028160722, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1383839921) 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, 691919990 + 691919991.

It is an arithmetic number, because the mean of its divisors is an integer number (691919991).

Almost surely, 2^1383839981 is an apocalyptic number.

It is an amenable number.

1383839981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1383839981 is an equidigital number, since it uses as much as digits as its factorization.

1383839981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1119744, while the sum is 53.

The square root of 1383839981 is about 37199.9997446237. Note that the first 3 decimals coincide. The cubic root of 1383839981 is about 1114.3679798089.

The spelling of 1383839981 in words is "one billion, three hundred eighty-three million, eight hundred thirty-nine thousand, nine hundred eighty-one".