561240 has 48 divisors (see below), whose sum is σ = 1825200. Its totient is φ = 149568.

The previous prime is 561229. The next prime is 561251. The reversal of 561240 is 42165.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (561229) and next prime (561251).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

561240 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 11 ways as a sum of consecutive naturals, for example, 420 + ... + 1139.

It is an arithmetic number, because the mean of its divisors is an integer number (38025).

2⁵⁶¹²⁴⁰ is an apocalyptic number.

It is an amenable number.

561240 is an abundant number, since it is smaller than the sum of its proper divisors (1263960).

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

561240 is a wasteful number, since it uses less digits than its factorization.

561240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1576 (or 1569 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 561240 is about 749.1595290724. The cubic root of 561240 is about 82.4864991682.

It can be divided in two parts, 56 and 1240, that added together give a 4-th power (1296 = 6⁴).

The spelling of 561240 in words is "five hundred sixty-one thousand, two hundred forty".