21102201191 has 4 divisors (see below), whose sum is σ = 21231662712. Its totient is φ = 20972739672.

The previous prime is 21102201187. The next prime is 21102201217. The reversal of 21102201191 is 19110220112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21102201191 - 2² = 21102201187 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21102201101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64730516 + ... + 64730841.

It is an arithmetic number, because the mean of its divisors is an integer number (5307915678).

Almost surely, 2^21102201191 is an apocalyptic number.

21102201191 is a deficient number, since it is larger than the sum of its proper divisors (129461521).

21102201191 is a wasteful number, since it uses less digits than its factorization.

21102201191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129461520.

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

The spelling of 21102201191 in words is "twenty-one billion, one hundred two million, two hundred one thousand, one hundred ninety-one".