1001995992 has 72 divisors (see below), whose sum is σ = 2735557500. Its totient is φ = 331333344.

The previous prime is 1001995979. The next prime is 1001995993. The reversal of 1001995992 is 2995991001.

It is a tau number, because it is divible by the number of its divisors (72).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1001995993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 2007759 + ... + 2008257.

Almost surely, 2^1001995992 is an apocalyptic number.

1001995992 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1001995992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1367778750).

1001995992 is an abundant number, since it is smaller than the sum of its proper divisors (1733561508).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1001995992 is a wasteful number, since it uses less digits than its factorization.

1001995992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 845 (or 671 counting only the distinct ones).

The product of its (nonzero) digits is 65610, while the sum is 45.

The square root of 1001995992 is about 31654.3202738584. The cubic root of 1001995992 is about 1000.6648884920.

The spelling of 1001995992 in words is "one billion, one million, nine hundred ninety-five thousand, nine hundred ninety-two".