191000100 has 108 divisors (see below), whose sum is σ = 587313104. Its totient is φ = 47915520.

The previous prime is 191000093. The next prime is 191000101. The reversal of 191000100 is 1000191.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is not an unprimeable number, because it can be changed into a prime (191000101) by changing a digit.

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 35 ways as a sum of consecutive naturals, for example, 85599 + ... + 87801.

Almost surely, 2^191000100 is an apocalyptic number.

191000100 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 191000100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (293656552).

191000100 is an abundant number, since it is smaller than the sum of its proper divisors (396313004).

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

191000100 is a wasteful number, since it uses less digits than its factorization.

191000100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2254 (or 2230 counting only the distinct ones).

The product of its (nonzero) digits is 9, while the sum is 12.

The square root of 191000100 is about 13820.2785789578. The cubic root of 191000100 is about 575.8966225547.

Adding to 191000100 its reverse (1000191), we get a palindrome (192000291).

The spelling of 191000100 in words is "one hundred ninety-one million, one hundred", and thus it is an aban number.