561331320 has 64 divisors (see below), whose sum is σ = 1837088640. Its totient is φ = 136080000.

The previous prime is 561331319. The next prime is 561331327. The reversal of 561331320 is 23133165.

It is a happy number.

561331320 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 (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561331327) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 211306 + ... + 213945.

It is an arithmetic number, because the mean of its divisors is an integer number (28704510).

Almost surely, 2^561331320 is an apocalyptic number.

It is an amenable number.

561331320 is an abundant number, since it is smaller than the sum of its proper divisors (1275757320).

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

561331320 is a wasteful number, since it uses less digits than its factorization.

561331320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 425276 (or 425272 counting only the distinct ones).

The product of its (nonzero) digits is 1620, while the sum is 24.

The square root of 561331320 is about 23692.4317029722. The cubic root of 561331320 is about 824.9097274964.

Adding to 561331320 its reverse (23133165), we get a palindrome (584464485).

The spelling of 561331320 in words is "five hundred sixty-one million, three hundred thirty-one thousand, three hundred twenty".