21374326443517 has 4 divisors (see below), whose sum is σ = 21594680324476. Its totient is φ = 21153972562560.

The previous prime is 21374326443473. The next prime is 21374326443541. The reversal of 21374326443517 is 71534462347312.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 16406112798916 + 4968213644601 = 4050446^2 + 2228949^2 .

It is a cyclic number.

It is not a de Polignac number, because 21374326443517 - 2²³ = 21374318054909 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 (21374326443017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 110176940334 + ... + 110176940527.

It is an arithmetic number, because the mean of its divisors is an integer number (5398670081119).

Almost surely, 2^{21374326443517} is an apocalyptic number.

It is an amenable number.

21374326443517 is a deficient number, since it is larger than the sum of its proper divisors (220353880959).

21374326443517 is an equidigital number, since it uses as much as digits as its factorization.

21374326443517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 220353880958.

The product of its digits is 10160640, while the sum is 52.

The spelling of 21374326443517 in words is "twenty-one trillion, three hundred seventy-four billion, three hundred twenty-six million, four hundred forty-three thousand, five hundred seventeen".