21085827477179 has 2 divisors, whose sum is σ = 21085827477180. Its totient is φ = 21085827477178.

The previous prime is 21085827477133. The next prime is 21085827477199. The reversal of 21085827477179 is 97177472858012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21085827477179 - 2²⁴ = 21085810699963 is a prime.

It is a super-2 number, since 2×21085827477179² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21085827477199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10542913738589 + 10542913738590.

It is an arithmetic number, because the mean of its divisors is an integer number (10542913738590).

Almost surely, 2^{21085827477179} is an apocalyptic number.

21085827477179 is a deficient number, since it is larger than the sum of its proper divisors (1).

21085827477179 is an equidigital number, since it uses as much as digits as its factorization.

21085827477179 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 110638080, while the sum is 68.

The spelling of 21085827477179 in words is "twenty-one trillion, eighty-five billion, eight hundred twenty-seven million, four hundred seventy-seven thousand, one hundred seventy-nine".