21145309876879 has 2 divisors, whose sum is σ = 21145309876880. Its totient is φ = 21145309876878.

The previous prime is 21145309876819. The next prime is 21145309876921. The reversal of 21145309876879 is 97867890354112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21145309876879 - 2²³ = 21145301488271 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21145309876819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10572654938439 + 10572654938440.

It is an arithmetic number, because the mean of its divisors is an integer number (10572654938440).

It is a 2-persistent number, because it is pandigital, and so is 2⋅21145309876879 = 42290619753758, but 3⋅21145309876879 = 63435929630637 is not.

Almost surely, 2^{21145309876879} is an apocalyptic number.

21145309876879 is a deficient number, since it is larger than the sum of its proper divisors (1).

21145309876879 is an equidigital number, since it uses as much as digits as its factorization.

21145309876879 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 182891520, while the sum is 70.

The spelling of 21145309876879 in words is "twenty-one trillion, one hundred forty-five billion, three hundred nine million, eight hundred seventy-six thousand, eight hundred seventy-nine".