561890 has 32 divisors (see below), whose sum is σ = 1209600. Its totient is φ = 183744.

The previous prime is 561839. The next prime is 561907. The reversal of 561890 is 98165.

561890 = 28² + 29² + ... + 119².

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 561890.

It is an unprimeable number.

561890 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, 1436 + ... + 1784.

It is an arithmetic number, because the mean of its divisors is an integer number (37800).

2⁵⁶¹⁸⁹⁰ is an apocalyptic number.

561890 is an abundant number, since it is smaller than the sum of its proper divisors (647710).

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

561890 is a wasteful number, since it uses less digits than its factorization.

561890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 386.

The product of its (nonzero) digits is 2160, while the sum is 29.

The square root of 561890 is about 749.5932230217. The cubic root of 561890 is about 82.5183307905.

The spelling of 561890 in words is "five hundred sixty-one thousand, eight hundred ninety".