521400 has 96 divisors (see below), whose sum is σ = 1785600. Its totient is φ = 124800.

The previous prime is 521399. The next prime is 521401. The reversal of 521400 is 4125.

521400 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (521399) and next prime (521401).

It is a Harshad number since it is a multiple of its sum of digits (12).

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (521401) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6561 + ... + 6639.

It is an arithmetic number, because the mean of its divisors is an integer number (18600).

2⁵²¹⁴⁰⁰ is an apocalyptic number.

521400 is a gapful number since it is divisible by the number (50) 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 521400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (892800).

521400 is an abundant number, since it is smaller than the sum of its proper divisors (1264200).

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

521400 is a wasteful number, since it uses less digits than its factorization.

521400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109 (or 100 counting only the distinct ones).

The product of its (nonzero) digits is 40, while the sum is 12.

The square root of 521400 is about 722.0803279414. The cubic root of 521400 is about 80.4866173759.

Adding to 521400 its reverse (4125), we get a palindrome (525525).

The spelling of 521400 in words is "five hundred twenty-one thousand, four hundred".