100000191920 has 80 divisors (see below), whose sum is σ = 240726958560. Its totient is φ = 38587164672.

The previous prime is 100000191919. The next prime is 100000191979. The reversal of 100000191920 is 29191000001.

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 2735684 + ... + 2771996.

It is an arithmetic number, because the mean of its divisors is an integer number (3009086982).

Almost surely, 2^100000191920 is an apocalyptic number.

100000191920 is a gapful number since it is divisible by the number (10) 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 100000191920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (120363479280).

100000191920 is an abundant number, since it is smaller than the sum of its proper divisors (140726766640).

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

100000191920 is a wasteful number, since it uses less digits than its factorization.

100000191920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37542 (or 37536 counting only the distinct ones).

The product of its (nonzero) digits is 162, while the sum is 23.

Adding to 100000191920 its reverse (29191000001), we get a palindrome (129191191921).

The spelling of 100000191920 in words is "one hundred billion, one hundred ninety-one thousand, nine hundred twenty".