402789 has 4 divisors (see below), whose sum is σ = 537056. Its totient is φ = 268524.

The previous prime is 402769. The next prime is 402797. The reversal of 402789 is 987204.

402789 = 141² + 142² + ... + 158².

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 402789 - 2⁵ = 402757 is a prime.

It is a D-number.

It is a Duffinian number.

It is a plaindrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (402739) 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, 67129 + ... + 67134.

It is an arithmetic number, because the mean of its divisors is an integer number (134264).

2⁴⁰²⁷⁸⁹ is an apocalyptic number.

It is an amenable number.

402789 is a deficient number, since it is larger than the sum of its proper divisors (134267).

402789 is a wasteful number, since it uses less digits than its factorization.

402789 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134266.

The product of its (nonzero) digits is 4032, while the sum is 30.

The square root of 402789 is about 634.6566000602. The cubic root of 402789 is about 73.8514795672.

The spelling of 402789 in words is "four hundred two thousand, seven hundred eighty-nine".