21385677084391 has 2 divisors, whose sum is σ = 21385677084392. Its totient is φ = 21385677084390.

The previous prime is 21385677084353. The next prime is 21385677084407. The reversal of 21385677084391 is 19348077658312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21385677084391 - 2¹⁵ = 21385677051623 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21385677082391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10692838542195 + 10692838542196.

It is an arithmetic number, because the mean of its divisors is an integer number (10692838542196).

It is a 1-persistent number, because it is pandigital, but 2⋅21385677084391 = 42771354168782 is not.

Almost surely, 2^{21385677084391} is an apocalyptic number.

21385677084391 is a deficient number, since it is larger than the sum of its proper divisors (1).

21385677084391 is an equidigital number, since it uses as much as digits as its factorization.

21385677084391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 60963840, while the sum is 64.

The spelling of 21385677084391 in words is "twenty-one trillion, three hundred eighty-five billion, six hundred seventy-seven million, eighty-four thousand, three hundred ninety-one".