1001995139 has 4 divisors (see below), whose sum is σ = 1005561240. Its totient is φ = 998429040.

The previous prime is 1001995133. The next prime is 1001995151. The reversal of 1001995139 is 9315991001.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 1001995139 - 2⁴ = 1001995123 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1001995133) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1782629 + ... + 1783190.

It is an arithmetic number, because the mean of its divisors is an integer number (251390310).

Almost surely, 2^1001995139 is an apocalyptic number.

1001995139 is a deficient number, since it is larger than the sum of its proper divisors (3566101).

1001995139 is an equidigital number, since it uses as much as digits as its factorization.

1001995139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3566100.

The product of its (nonzero) digits is 10935, while the sum is 38.

The square root of 1001995139 is about 31654.3068001812. The cubic root of 1001995139 is about 1000.6646045363.

The spelling of 1001995139 in words is "one billion, one million, nine hundred ninety-five thousand, one hundred thirty-nine".