401243105420221 has 4 divisors (see below), whose sum is σ = 407820861246844. Its totient is φ = 394665349593600.

The previous prime is 401243105420203. The next prime is 401243105420299. The reversal of 401243105420221 is 122024501342104.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 88742523105625 + 312500582314596 = 9420325^2 + 17677686^2 .

It is a cyclic number.

It is not a de Polignac number, because 401243105420221 - 2¹¹ = 401243105418173 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (401243105420321) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3288877913220 + ... + 3288877913341.

It is an arithmetic number, because the mean of its divisors is an integer number (101955215311711).

Almost surely, 2^{401243105420221} is an apocalyptic number.

It is an amenable number.

401243105420221 is a deficient number, since it is larger than the sum of its proper divisors (6577755826623).

401243105420221 is an equidigital number, since it uses as much as digits as its factorization.

401243105420221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6577755826622.

The product of its (nonzero) digits is 15360, while the sum is 31.

Adding to 401243105420221 its reverse (122024501342104), we get a palindrome (523267606762325).

The spelling of 401243105420221 in words is "four hundred one trillion, two hundred forty-three billion, one hundred five million, four hundred twenty thousand, two hundred twenty-one".