84390 has 32 divisors (see below), whose sum is σ = 211680. Its totient is φ = 21504.

The previous prime is 84389. The next prime is 84391. The reversal of 84390 is 9348.

It is an interprime number because it is at equal distance from previous prime (84389) and next prime (84391).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 84390.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (84391) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 822 + ... + 918.

It is an arithmetic number, because the mean of its divisors is an integer number (6615).

2⁸⁴³⁹⁰ is an apocalyptic number.

It is a pronic number, being equal to 290×291.

It is a practical number, because each smaller number is the sum of distinct divisors of 84390, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (105840).

84390 is an abundant number, since it is smaller than the sum of its proper divisors (127290).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

84390 is a wasteful number, since it uses less digits than its factorization.

84390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136.

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 84390 is about 290.4995697071. The cubic root of 84390 is about 43.8628650461.

It can be divided in two parts, 84 and 390, that added together give a palindrome (474).

The spelling of 84390 in words is "eighty-four thousand, three hundred ninety".