21810842048117 has 4 divisors (see below), whose sum is σ = 21811958797056. Its totient is φ = 21809725299180.

The previous prime is 21810842048057. The next prime is 21810842048131. The reversal of 21810842048117 is 71184024801812.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21810842048117 - 2¹² = 21810842044021 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 (21810842048137) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 558345173 + ... + 558384234.

It is an arithmetic number, because the mean of its divisors is an integer number (5452989699264).

Almost surely, 2^{21810842048117} is an apocalyptic number.

It is an amenable number.

21810842048117 is a deficient number, since it is larger than the sum of its proper divisors (1116748939).

21810842048117 is a wasteful number, since it uses less digits than its factorization.

21810842048117 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1116748938.

The product of its (nonzero) digits is 229376, while the sum is 47.

Adding to 21810842048117 its reverse (71184024801812), we get a palindrome (92994866849929).

The spelling of 21810842048117 in words is "twenty-one trillion, eight hundred ten billion, eight hundred forty-two million, forty-eight thousand, one hundred seventeen".