100991232 has 144 divisors (see below), whose sum is σ = 314776000. Its totient is φ = 31850496.

The previous prime is 100991207. The next prime is 100991239. The reversal of 100991232 is 232199001.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 100991196 and 100991205.

It is not an unprimeable number, because it can be changed into a prime (100991239) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 130944 + ... + 131712.

Almost surely, 2^100991232 is an apocalyptic number.

100991232 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 100991232, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (157388000).

100991232 is an abundant number, since it is smaller than the sum of its proper divisors (213784768).

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

100991232 is an equidigital number, since it uses as much as digits as its factorization.

100991232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 813 (or 793 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 27.

The square root of 100991232 is about 10049.4393873489. The cubic root of 100991232 is about 465.6874742652.

The spelling of 100991232 in words is "one hundred million, nine hundred ninety-one thousand, two hundred thirty-two".