402739609 has 2 divisors, whose sum is σ = 402739610. Its totient is φ = 402739608.

The previous prime is 402739577. The next prime is 402739669. The reversal of 402739609 is 906937204.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 348643584 + 54096025 = 18672^2 + 7355^2 .

It is a cyclic number.

It is not a de Polignac number, because 402739609 - 2⁵ = 402739577 is a prime.

It is not a weakly prime, because it can be changed into another prime (402739669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 201369804 + 201369805.

It is an arithmetic number, because the mean of its divisors is an integer number (201369805).

Almost surely, 2^402739609 is an apocalyptic number.

It is an amenable number.

402739609 is a deficient number, since it is larger than the sum of its proper divisors (1).

402739609 is an equidigital number, since it uses as much as digits as its factorization.

402739609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 81648, while the sum is 40.

The square root of 402739609 is about 20068.3733521180. The cubic root of 402739609 is about 738.4846082573.

The spelling of 402739609 in words is "four hundred two million, seven hundred thirty-nine thousand, six hundred nine".