21471120191 has 2 divisors, whose sum is σ = 21471120192. Its totient is φ = 21471120190.

The previous prime is 21471120161. The next prime is 21471120257. The reversal of 21471120191 is 19102117412.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21471120191 - 2⁶ = 21471120127 is a prime.

It is a super-2 number, since 2×21471120191² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21471120161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10735560095 + 10735560096.

It is an arithmetic number, because the mean of its divisors is an integer number (10735560096).

Almost surely, 2^21471120191 is an apocalyptic number.

21471120191 is a deficient number, since it is larger than the sum of its proper divisors (1).

21471120191 is an equidigital number, since it uses as much as digits as its factorization.

21471120191 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1008, while the sum is 29.

The spelling of 21471120191 in words is "twenty-one billion, four hundred seventy-one million, one hundred twenty thousand, one hundred ninety-one".