401205521 has 2 divisors, whose sum is σ = 401205522. Its totient is φ = 401205520.

The previous prime is 401205499. The next prime is 401205533. The reversal of 401205521 is 125502104.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 388878400 + 12327121 = 19720^2 + 3511^2 .

It is a cyclic number.

It is not a de Polignac number, because 401205521 - 2²⁶ = 334096657 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 401205493 and 401205502.

It is not a weakly prime, because it can be changed into another prime (401202521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200602760 + 200602761.

It is an arithmetic number, because the mean of its divisors is an integer number (200602761).

Almost surely, 2^401205521 is an apocalyptic number.

It is an amenable number.

401205521 is a deficient number, since it is larger than the sum of its proper divisors (1).

401205521 is an equidigital number, since it uses as much as digits as its factorization.

401205521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 400, while the sum is 20.

The square root of 401205521 is about 20030.1153516399. The cubic root of 401205521 is about 737.5457535916.

Adding to 401205521 its reverse (125502104), we get a palindrome (526707625).

The spelling of 401205521 in words is "four hundred one million, two hundred five thousand, five hundred twenty-one".