1138631609 has 2 divisors, whose sum is σ = 1138631610. Its totient is φ = 1138631608.

The previous prime is 1138631603. The next prime is 1138631617. The reversal of 1138631609 is 9061368311.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 848440384 + 290191225 = 29128^2 + 17035^2 .

It is an emirp because it is prime and its reverse (9061368311) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1138631609 - 2¹⁶ = 1138566073 is a prime.

It is not a weakly prime, because it can be changed into another prime (1138631603) 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 as a sum of consecutive naturals, namely, 569315804 + 569315805.

It is an arithmetic number, because the mean of its divisors is an integer number (569315805).

Almost surely, 2^1138631609 is an apocalyptic number.

It is an amenable number.

1138631609 is a deficient number, since it is larger than the sum of its proper divisors (1).

1138631609 is an equidigital number, since it uses as much as digits as its factorization.

1138631609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 23328, while the sum is 38.

The square root of 1138631609 is about 33743.6158258121. The cubic root of 1138631609 is about 1044.2257824699.

The spelling of 1138631609 in words is "one billion, one hundred thirty-eight million, six hundred thirty-one thousand, six hundred nine".