84780 has 48 divisors (see below), whose sum is σ = 265440. Its totient is φ = 22464.

The previous prime is 84761. The next prime is 84787. The reversal of 84780 is 8748.

Added to its reverse (8748) it gives a triangular number (93528 = T₄₃₂).

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (84787) 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, 462 + ... + 618.

It is an arithmetic number, because the mean of its divisors is an integer number (5530).

2⁸⁴⁷⁸⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 84780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (132720).

84780 is an abundant number, since it is smaller than the sum of its proper divisors (180660).

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

84780 is a wasteful number, since it uses less digits than its factorization.

84780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175 (or 167 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 27.

The square root of 84780 is about 291.1700534052. The cubic root of 84780 is about 43.9303305151.

Adding to 84780 its reverse (8748), we get a triangular number (93528 = T₄₃₂).

The spelling of 84780 in words is "eighty-four thousand, seven hundred eighty".