21550427243407 has 2 divisors, whose sum is σ = 21550427243408. Its totient is φ = 21550427243406.

The previous prime is 21550427243399. The next prime is 21550427243459. The reversal of 21550427243407 is 70434272405512.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21550427243407 - 2³ = 21550427243399 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21550427243707) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10775213621703 + 10775213621704.

It is an arithmetic number, because the mean of its divisors is an integer number (10775213621704).

Almost surely, 2^{21550427243407} is an apocalyptic number.

21550427243407 is a deficient number, since it is larger than the sum of its proper divisors (1).

21550427243407 is an equidigital number, since it uses as much as digits as its factorization.

21550427243407 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1881600, while the sum is 46.

Adding to 21550427243407 its reverse (70434272405512), we get a palindrome (91984699648919).

The spelling of 21550427243407 in words is "twenty-one trillion, five hundred fifty billion, four hundred twenty-seven million, two hundred forty-three thousand, four hundred seven".