1138238818 has 4 divisors (see below), whose sum is σ = 1707358230. Its totient is φ = 569119408.

The previous prime is 1138238779. The next prime is 1138238821. The reversal of 1138238818 is 8188328311.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8188328311 = 15359 ⋅533129.

It can be written as a sum of positive squares in only one way, i.e., 986776569 + 151462249 = 31413^2 + 12307^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 284559703 + ... + 284559706.

Almost surely, 2^1138238818 is an apocalyptic number.

1138238818 is a deficient number, since it is larger than the sum of its proper divisors (569119412).

1138238818 is an equidigital number, since it uses as much as digits as its factorization.

1138238818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 569119411.

The product of its digits is 73728, while the sum is 43.

The square root of 1138238818 is about 33737.7950968939. The cubic root of 1138238818 is about 1044.1056939767.

The spelling of 1138238818 in words is "one billion, one hundred thirty-eight million, two hundred thirty-eight thousand, eight hundred eighteen".