21243164444587 has 2 divisors, whose sum is σ = 21243164444588. Its totient is φ = 21243164444586.

The previous prime is 21243164444573. The next prime is 21243164444603. The reversal of 21243164444587 is 78544446134212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21243164444587 - 2⁷ = 21243164444459 is a prime.

It is not a weakly prime, because it can be changed into another prime (21243165444587) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10621582222293 + 10621582222294.

It is an arithmetic number, because the mean of its divisors is an integer number (10621582222294).

Almost surely, 2^{21243164444587} is an apocalyptic number.

21243164444587 is a deficient number, since it is larger than the sum of its proper divisors (1).

21243164444587 is an equidigital number, since it uses as much as digits as its factorization.

21243164444587 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20643840, while the sum is 55.

The spelling of 21243164444587 in words is "twenty-one trillion, two hundred forty-three billion, one hundred sixty-four million, four hundred forty-four thousand, five hundred eighty-seven".