21122503402177 has 2 divisors, whose sum is σ = 21122503402178. Its totient is φ = 21122503402176.

The previous prime is 21122503402111. The next prime is 21122503402181. The reversal of 21122503402177 is 77120430522112.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11151585681201 + 9970917720976 = 3339399^2 + 3157676^2 .

It is a cyclic number.

It is not a de Polignac number, because 21122503402177 - 2¹¹ = 21122503400129 is a prime.

It is not a weakly prime, because it can be changed into another prime (21122503406177) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10561251701088 + 10561251701089.

It is an arithmetic number, because the mean of its divisors is an integer number (10561251701089).

Almost surely, 2^{21122503402177} is an apocalyptic number.

It is an amenable number.

21122503402177 is a deficient number, since it is larger than the sum of its proper divisors (1).

21122503402177 is an equidigital number, since it uses as much as digits as its factorization.

21122503402177 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 47040, while the sum is 37.

Adding to 21122503402177 its reverse (77120430522112), we get a palindrome (98242933924289).

The spelling of 21122503402177 in words is "twenty-one trillion, one hundred twenty-two billion, five hundred three million, four hundred two thousand, one hundred seventy-seven".