840002 has 4 divisors (see below), whose sum is σ = 1260006. Its totient is φ = 420000.

The previous prime is 839999. The next prime is 840023. The reversal of 840002 is 200048.

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

It can be written as a sum of positive squares in only one way, i.e., 638401 + 201601 = 799^2 + 449^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 209999 + ... + 210002.

2⁸⁴⁰⁰⁰² is an apocalyptic number.

840002 is a deficient number, since it is larger than the sum of its proper divisors (420004).

840002 is a wasteful number, since it uses less digits than its factorization.

840002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 420003.

The product of its (nonzero) digits is 64, while the sum is 14.

The square root of 840002 is about 916.5162300800. The cubic root of 840002 is about 94.3539544903.

Subtracting from 840002 its product of nonzero digits (64), we obtain a palindrome (839938).

The spelling of 840002 in words is "eight hundred forty thousand, two".