402289 has 4 divisors (see below), whose sum is σ = 403956. Its totient is φ = 400624.

The previous prime is 402277. The next prime is 402299. The reversal of 402289 is 982204.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 390625 + 11664 = 625^2 + 108^2 .

It is a cyclic number.

It is not a de Polignac number, because 402289 - 2¹⁷ = 271217 is a prime.

It is a Duffinian number.

402289 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (402239) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 394 + ... + 979.

It is an arithmetic number, because the mean of its divisors is an integer number (100989).

2⁴⁰²²⁸⁹ is an apocalyptic number.

It is an amenable number.

402289 is a deficient number, since it is larger than the sum of its proper divisors (1667).

402289 is a wasteful number, since it uses less digits than its factorization.

402289 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1666.

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 402289 is about 634.2625639276. The cubic root of 402289 is about 73.8209085324.

The spelling of 402289 in words is "four hundred two thousand, two hundred eighty-nine".