557820 has 48 divisors (see below), whose sum is σ = 1737120. Its totient is φ = 148608.

The previous prime is 557803. The next prime is 557831. The reversal of 557820 is 28755.

557820 = T₃₂₉ + T₃₃₀ + ... + T₃₃₈.

It is a happy number.

It is a super-2 number, since 2×557820² = 622326304800, which contains 22 as substring.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24 + ... + 1056.

It is an arithmetic number, because the mean of its divisors is an integer number (36190).

2⁵⁵⁷⁸²⁰ 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 557820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (868560).

557820 is an abundant number, since it is smaller than the sum of its proper divisors (1179300).

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

557820 is a wasteful number, since it uses less digits than its factorization.

557820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1051 (or 1043 counting only the distinct ones).

The product of its (nonzero) digits is 2800, while the sum is 27.

The square root of 557820 is about 746.8734832621. The cubic root of 557820 is about 82.3186097395.

It can be divided in two parts, 55 and 7820, that added together give a triangular number (7875 = T₁₂₅).

The spelling of 557820 in words is "five hundred fifty-seven thousand, eight hundred twenty".