20421120440167 has 2 divisors, whose sum is σ = 20421120440168. Its totient is φ = 20421120440166.

The previous prime is 20421120440131. The next prime is 20421120440317. The reversal of 20421120440167 is 76104402112402.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20421120440167 - 2³¹ = 20418972956519 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20421120440117) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10210560220083 + 10210560220084.

It is an arithmetic number, because the mean of its divisors is an integer number (10210560220084).

Almost surely, 2^{20421120440167} is an apocalyptic number.

20421120440167 is a deficient number, since it is larger than the sum of its proper divisors (1).

20421120440167 is an equidigital number, since it uses as much as digits as its factorization.

20421120440167 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21504, while the sum is 34.

Adding to 20421120440167 its reverse (76104402112402), we get a palindrome (96525522552569).

The spelling of 20421120440167 in words is "twenty trillion, four hundred twenty-one billion, one hundred twenty million, four hundred forty thousand, one hundred sixty-seven".