1001001955 has 4 divisors (see below), whose sum is σ = 1201202352. Its totient is φ = 800801560.

The previous prime is 1001001923. The next prime is 1001002001. The reversal of 1001001955 is 5591001001.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5591001001 = 31 ⋅180354871.

It is not a de Polignac number, because 1001001955 - 2⁵ = 1001001923 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

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 in 3 ways as a sum of consecutive naturals, for example, 100100191 + ... + 100100200.

It is an arithmetic number, because the mean of its divisors is an integer number (300300588).

Almost surely, 2^1001001955 is an apocalyptic number.

1001001955 is a deficient number, since it is larger than the sum of its proper divisors (200200397).

1001001955 is an equidigital number, since it uses as much as digits as its factorization.

1001001955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200200396.

The product of its (nonzero) digits is 225, while the sum is 22.

The square root of 1001001955 is about 31638.6149349177. The cubic root of 1001001955 is about 1000.3338735161. Note that the first 3 decimals are identical.

Adding to 1001001955 its reverse (5591001001), we get a palindrome (6592002956).

The spelling of 1001001955 in words is "one billion, one million, one thousand, nine hundred fifty-five".