21255601002667 has 2 divisors, whose sum is σ = 21255601002668. Its totient is φ = 21255601002666.

The previous prime is 21255601002577. The next prime is 21255601002679. The reversal of 21255601002667 is 76620010655212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21255601002667 - 2¹⁹ = 21255600478379 is a prime.

It is a super-2 number, since 2×21255601002667² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21255601002067) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10627800501333 + 10627800501334.

It is an arithmetic number, because the mean of its divisors is an integer number (10627800501334).

Almost surely, 2^{21255601002667} is an apocalyptic number.

21255601002667 is a deficient number, since it is larger than the sum of its proper divisors (1).

21255601002667 is an equidigital number, since it uses as much as digits as its factorization.

21255601002667 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 302400, while the sum is 43.

Adding to 21255601002667 its reverse (76620010655212), we get a palindrome (97875611657879).

The spelling of 21255601002667 in words is "twenty-one trillion, two hundred fifty-five billion, six hundred one million, two thousand, six hundred sixty-seven".