221623436322401 has 2 divisors, whose sum is σ = 221623436322402. Its totient is φ = 221623436322400.

The previous prime is 221623436322271. The next prime is 221623436322403. The reversal of 221623436322401 is 104223634326122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 200428010707600 + 21195425614801 = 14157260^2 + 4603849^2 .

It is a cyclic number.

It is not a de Polignac number, because 221623436322401 - 2²² = 221623432128097 is a prime.

It is a super-2 number, since 2×221623436322401² (a number of 29 digits) contains 22 as substring.

It is a Sophie Germain prime.

Together with 221623436322403, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (221623436322403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110811718161200 + 110811718161201.

It is an arithmetic number, because the mean of its divisors is an integer number (110811718161201).

Almost surely, 2^{221623436322401} is an apocalyptic number.

It is an amenable number.

221623436322401 is a deficient number, since it is larger than the sum of its proper divisors (1).

221623436322401 is an equidigital number, since it uses as much as digits as its factorization.

221623436322401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 497664, while the sum is 41.

The spelling of 221623436322401 in words is "two hundred twenty-one trillion, six hundred twenty-three billion, four hundred thirty-six million, three hundred twenty-two thousand, four hundred one".