1001231138 has 4 divisors (see below), whose sum is σ = 1501846710. Its totient is φ = 500615568.

The previous prime is 1001231131. The next prime is 1001231159. The reversal of 1001231138 is 8311321001.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 769674049 + 231557089 = 27743^2 + 15217^2 .

It is not an unprimeable number, because it can be changed into a prime (1001231131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 250307783 + ... + 250307786.

Almost surely, 2^1001231138 is an apocalyptic number.

1001231138 is a deficient number, since it is larger than the sum of its proper divisors (500615572).

1001231138 is an equidigital number, since it uses as much as digits as its factorization.

1001231138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 500615571.

The product of its (nonzero) digits is 144, while the sum is 20.

The square root of 1001231138 is about 31642.2366150056. The cubic root of 1001231138 is about 1000.4102110372.

Adding to 1001231138 its reverse (8311321001), we get a palindrome (9312552139).

The spelling of 1001231138 in words is "one billion, one million, two hundred thirty-one thousand, one hundred thirty-eight".