21523958044917 has 4 divisors (see below), whose sum is σ = 28698610726560. Its totient is φ = 14349305363276.

The previous prime is 21523958044861. The next prime is 21523958044949. The reversal of 21523958044917 is 71944085932512.

It is a happy number.

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 21523958044917 - 2¹¹ = 21523958042869 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21523958044417) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3587326340817 + ... + 3587326340822.

It is an arithmetic number, because the mean of its divisors is an integer number (7174652681640).

Almost surely, 2^{21523958044917} is an apocalyptic number.

It is an amenable number.

21523958044917 is a deficient number, since it is larger than the sum of its proper divisors (7174652681643).

21523958044917 is an equidigital number, since it uses as much as digits as its factorization.

21523958044917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7174652681642.

The product of its (nonzero) digits is 21772800, while the sum is 60.

The spelling of 21523958044917 in words is "twenty-one trillion, five hundred twenty-three billion, nine hundred fifty-eight million, forty-four thousand, nine hundred seventeen".