402206521 has 2 divisors, whose sum is σ = 402206522. Its totient is φ = 402206520.

The previous prime is 402206491. The next prime is 402206579. The reversal of 402206521 is 125602204.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 401802025 + 404496 = 20045^2 + 636^2 .

It is a cyclic number.

It is not a de Polignac number, because 402206521 - 2⁷ = 402206393 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 402206492 and 402206501.

It is not a weakly prime, because it can be changed into another prime (402206921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 201103260 + 201103261.

It is an arithmetic number, because the mean of its divisors is an integer number (201103261).

Almost surely, 2^402206521 is an apocalyptic number.

It is an amenable number.

402206521 is a deficient number, since it is larger than the sum of its proper divisors (1).

402206521 is an equidigital number, since it uses as much as digits as its factorization.

402206521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 960, while the sum is 22.

The square root of 402206521 is about 20055.0871601197. The cubic root of 402206521 is about 738.1586316217.

Adding to 402206521 its reverse (125602204), we get a palindrome (527808725).

The spelling of 402206521 in words is "four hundred two million, two hundred six thousand, five hundred twenty-one".