684955 has 4 divisors (see below), whose sum is σ = 821952. Its totient is φ = 547960.

The previous prime is 684949. The next prime is 684961. The reversal of 684955 is 559486.

684955 is nontrivially palindromic in base 9.

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

It is an interprime number because it is at equal distance from previous prime (684949) and next prime (684961).

It is not a de Polignac number, because 684955 - 2⁵ = 684923 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 68491 + ... + 68500.

It is an arithmetic number, because the mean of its divisors is an integer number (205488).

2⁶⁸⁴⁹⁵⁵ is an apocalyptic number.

684955 is a deficient number, since it is larger than the sum of its proper divisors (136997).

684955 is a wasteful number, since it uses less digits than its factorization.

684955 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136996.

The product of its digits is 43200, while the sum is 37.

The square root of 684955 is about 827.6200819217. The cubic root of 684955 is about 88.1496678257.

The spelling of 684955 in words is "six hundred eighty-four thousand, nine hundred fifty-five".