561039100 has 72 divisors (see below), whose sum is σ = 1293854688. Its totient is φ = 210432000.

The previous prime is 561039077. The next prime is 561039107. The reversal of 561039100 is 1930165.

561039100 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561039107) 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, 681289 + ... + 682111.

It is an arithmetic number, because the mean of its divisors is an integer number (17970204).

Almost surely, 2^561039100 is an apocalyptic number.

561039100 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 561039100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (646927344).

561039100 is an abundant number, since it is smaller than the sum of its proper divisors (732815588).

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

561039100 is a wasteful number, since it uses less digits than its factorization.

561039100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1255 (or 1248 counting only the distinct ones).

The product of its (nonzero) digits is 810, while the sum is 25.

The square root of 561039100 is about 23686.2639519195. The cubic root of 561039100 is about 824.7665577652.

Adding to 561039100 its reverse (1930165), we get a palindrome (562969265).

The spelling of 561039100 in words is "five hundred sixty-one million, thirty-nine thousand, one hundred".