21213544395779 has 2 divisors, whose sum is σ = 21213544395780. Its totient is φ = 21213544395778.

The previous prime is 21213544395773. The next prime is 21213544395851. The reversal of 21213544395779 is 97759344531212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21213544395779 - 2¹⁶ = 21213544330243 is a prime.

It is a super-3 number, since 3×21213544395779³ (a number of 41 digits) contains 333 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (21213544395773) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606772197889 + 10606772197890.

It is an arithmetic number, because the mean of its divisors is an integer number (10606772197890).

Almost surely, 2^{21213544395779} is an apocalyptic number.

21213544395779 is a deficient number, since it is larger than the sum of its proper divisors (1).

21213544395779 is an equidigital number, since it uses as much as digits as its factorization.

21213544395779 is an evil number, because the sum of its binary digits is even.

The product of its digits is 57153600, while the sum is 62.

The spelling of 21213544395779 in words is "twenty-one trillion, two hundred thirteen billion, five hundred forty-four million, three hundred ninety-five thousand, seven hundred seventy-nine".