21872918974079 has 2 divisors, whose sum is σ = 21872918974080. Its totient is φ = 21872918974078.

The previous prime is 21872918974033. The next prime is 21872918974097. The reversal of 21872918974079 is 97047981927812.

Together with next prime (21872918974097) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21872918974079 - 2¹² = 21872918969983 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21872918973997 and 21872918974015.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21872918974279) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10936459487039 + 10936459487040.

It is an arithmetic number, because the mean of its divisors is an integer number (10936459487040).

Almost surely, 2^{21872918974079} is an apocalyptic number.

21872918974079 is a deficient number, since it is larger than the sum of its proper divisors (1).

21872918974079 is an equidigital number, since it uses as much as digits as its factorization.

21872918974079 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 256048128, while the sum is 74.

The spelling of 21872918974079 in words is "twenty-one trillion, eight hundred seventy-two billion, nine hundred eighteen million, nine hundred seventy-four thousand, seventy-nine".