402532391 has 2 divisors, whose sum is σ = 402532392. Its totient is φ = 402532390.

The previous prime is 402532381. The next prime is 402532411. The reversal of 402532391 is 193235204.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-402532391 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (402532381) 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, 201266195 + 201266196.

It is an arithmetic number, because the mean of its divisors is an integer number (201266196).

Almost surely, 2^402532391 is an apocalyptic number.

402532391 is a deficient number, since it is larger than the sum of its proper divisors (1).

402532391 is an equidigital number, since it uses as much as digits as its factorization.

402532391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6480, while the sum is 29.

The square root of 402532391 is about 20063.2098877523. The cubic root of 402532391 is about 738.3579312407.

Adding to 402532391 its reverse (193235204), we get a palindrome (595767595).

The spelling of 402532391 in words is "four hundred two million, five hundred thirty-two thousand, three hundred ninety-one".