21878126479 has 8 divisors (see below), whose sum is σ = 25123207680. Its totient is φ = 18842405400.

The previous prime is 21878126453. The next prime is 21878126503. The reversal of 21878126479 is 97462187812.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21878126479 - 2⁷ = 21878126351 is a prime.

It is a super-2 number, since 2×21878126479² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21878126419) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 52339807 + ... + 52340224.

It is an arithmetic number, because the mean of its divisors is an integer number (3140400960).

Almost surely, 2^21878126479 is an apocalyptic number.

21878126479 is a deficient number, since it is larger than the sum of its proper divisors (3245081201).

21878126479 is a wasteful number, since it uses less digits than its factorization.

21878126479 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 104680061.

The product of its digits is 2709504, while the sum is 55.

The spelling of 21878126479 in words is "twenty-one billion, eight hundred seventy-eight million, one hundred twenty-six thousand, four hundred seventy-nine".