245820 has 48 divisors (see below), whose sum is σ = 731808. Its totient is φ = 61440.

The previous prime is 245789. The next prime is 245821. The reversal of 245820 is 28542.

It is a nialpdrome in base 12.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (245821) by changing a digit.

245820 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 900 + ... + 1140.

It is an arithmetic number, because the mean of its divisors is an integer number (15246).

2²⁴⁵⁸²⁰ is an apocalyptic number.

245820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 245820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (365904).

245820 is an abundant number, since it is smaller than the sum of its proper divisors (485988).

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

245820 is a wasteful number, since it uses less digits than its factorization.

245820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 270 (or 268 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 21.

The square root of 245820 is about 495.8023799862. The cubic root of 245820 is about 62.6429793278.

The spelling of 245820 in words is "two hundred forty-five thousand, eight hundred twenty".