191101421 has 16 divisors (see below), whose sum is σ = 224102400. Its totient is φ = 162887760.

The previous prime is 191101409. The next prime is 191101439. The reversal of 191101421 is 124101191.

It is not a de Polignac number, because 191101421 - 2¹⁸ = 190839277 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 191101393 and 191101402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (191101481) 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 15 ways as a sum of consecutive naturals, for example, 64055 + ... + 66971.

It is an arithmetic number, because the mean of its divisors is an integer number (14006400).

Almost surely, 2^191101421 is an apocalyptic number.

It is an amenable number.

191101421 is a deficient number, since it is larger than the sum of its proper divisors (33000979).

191101421 is an equidigital number, since it uses as much as digits as its factorization.

191101421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3129 (or 3115 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 20.

The square root of 191101421 is about 13823.9437571194. The cubic root of 191101421 is about 575.9984376967.

The spelling of 191101421 in words is "one hundred ninety-one million, one hundred one thousand, four hundred twenty-one".