402561217 has 2 divisors, whose sum is σ = 402561218. Its totient is φ = 402561216.

The previous prime is 402561193. The next prime is 402561223. The reversal of 402561217 is 712165204.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 395373456 + 7187761 = 19884^2 + 2681^2 .

It is a cyclic number.

It is not a de Polignac number, because 402561217 - 2¹¹ = 402559169 is a prime.

It is not a weakly prime, because it can be changed into another prime (402562217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 201280608 + 201280609.

It is an arithmetic number, because the mean of its divisors is an integer number (201280609).

Almost surely, 2^402561217 is an apocalyptic number.

It is an amenable number.

402561217 is a deficient number, since it is larger than the sum of its proper divisors (1).

402561217 is an equidigital number, since it uses as much as digits as its factorization.

402561217 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3360, while the sum is 28.

The square root of 402561217 is about 20063.9282544571. The cubic root of 402561217 is about 738.3755558246.

The spelling of 402561217 in words is "four hundred two million, five hundred sixty-one thousand, two hundred seventeen".