21202010191 has 2 divisors, whose sum is σ = 21202010192. Its totient is φ = 21202010190.

The previous prime is 21202010147. The next prime is 21202010201. The reversal of 21202010191 is 19101020212.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21202010191 - 2²¹ = 21199913039 is a prime.

It is a super-2 number, since 2×21202010191² (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 (21202010101) 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 as a sum of consecutive naturals, namely, 10601005095 + 10601005096.

It is an arithmetic number, because the mean of its divisors is an integer number (10601005096).

Almost surely, 2^21202010191 is an apocalyptic number.

21202010191 is a deficient number, since it is larger than the sum of its proper divisors (1).

21202010191 is an equidigital number, since it uses as much as digits as its factorization.

21202010191 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72, while the sum is 19.

The spelling of 21202010191 in words is "twenty-one billion, two hundred two million, ten thousand, one hundred ninety-one".