402421442393 has 2 divisors, whose sum is σ = 402421442394. Its totient is φ = 402421442392.

The previous prime is 402421442389. The next prime is 402421442491. The reversal of 402421442393 is 393244124204.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 401647935049 + 773507344 = 633757^2 + 27812^2 .

It is a cyclic number.

It is not a de Polignac number, because 402421442393 - 2² = 402421442389 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (402421442323) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 201210721196 + 201210721197.

It is an arithmetic number, because the mean of its divisors is an integer number (201210721197).

Almost surely, 2^402421442393 is an apocalyptic number.

It is an amenable number.

402421442393 is a deficient number, since it is larger than the sum of its proper divisors (1).

402421442393 is an equidigital number, since it uses as much as digits as its factorization.

402421442393 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 165888, while the sum is 38.

Adding to 402421442393 its reverse (393244124204), we get a palindrome (795665566597).

The spelling of 402421442393 in words is "four hundred two billion, four hundred twenty-one million, four hundred forty-two thousand, three hundred ninety-three".