561391280 has 40 divisors (see below), whose sum is σ = 1350248400. Its totient is φ = 216812288.

The previous prime is 561391267. The next prime is 561391297. The reversal of 561391280 is 82193165.

It is a tau number, because it is divible by the number of its divisors (40).

It is a self number, because there is not a number n which added to its sum of digits gives 561391280.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 118670 + ... + 123309.

It is an arithmetic number, because the mean of its divisors is an integer number (33756210).

Almost surely, 2^561391280 is an apocalyptic number.

It is an amenable number.

561391280 is an abundant number, since it is smaller than the sum of its proper divisors (788857120).

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

561391280 is a wasteful number, since it uses less digits than its factorization.

561391280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 242021 (or 242015 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 35.

The square root of 561391280 is about 23693.6970521698. The cubic root of 561391280 is about 824.9390980449.

The spelling of 561391280 in words is "five hundred sixty-one million, three hundred ninety-one thousand, two hundred eighty".