21155104199 has 2 divisors, whose sum is σ = 21155104200. Its totient is φ = 21155104198.

The previous prime is 21155104171. The next prime is 21155104213. The reversal of 21155104199 is 99140155112.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21155104199 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21155104169) 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, 10577552099 + 10577552100.

It is an arithmetic number, because the mean of its divisors is an integer number (10577552100).

Almost surely, 2^21155104199 is an apocalyptic number.

21155104199 is a deficient number, since it is larger than the sum of its proper divisors (1).

21155104199 is an equidigital number, since it uses as much as digits as its factorization.

21155104199 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16200, while the sum is 38.

The spelling of 21155104199 in words is "twenty-one billion, one hundred fifty-five million, one hundred four thousand, one hundred ninety-nine".