1001001001 has 32 divisors (see below), whose sum is σ = 1357445376. Its totient is φ = 712800000.

The previous prime is 1001000989. The next prime is 1001001011.

1001001001 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 1001001001 - 2¹¹ = 1000998953 is a prime.

1001001001 is a strobogrammatic number because it is the same when read upside-down.

It is a deceptive number, since it divides R_1001001000.

1001001001 is a modest number, since divided by 1001001 gives 1 as remainder.

It is not an unprimeable number, because it can be changed into a prime (1001001011) by changing a digit.

It is a nontrivial repunit in base 1000.

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 in 31 ways as a sum of consecutive naturals, for example, 96151 + ... + 106051.

It is an arithmetic number, because the mean of its divisors is an integer number (42420168).

Almost surely, 2^1001001001 is an apocalyptic number.

1001001001 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1001001001 is a deficient number, since it is larger than the sum of its proper divisors (356444375).

1001001001 is a wasteful number, since it uses less digits than its factorization.

1001001001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10033.

The product of its (nonzero) digits is 1, while the sum is 4.

The square root of 1001001001 is about 31638.5998584008. The cubic root of 1001001001 is about 1000.3335557282. Note that the first 3 decimals are identical.

It can be divided in two parts, 100100 and 1001, that multiplied together give a square (100200100 = 10010²).

The spelling of 1001001001 in words is "one billion, one million, one thousand, one".