561280665 has 32 divisors (see below), whose sum is σ = 980812800. Its totient is φ = 271824320.

The previous prime is 561280663. The next prime is 561280667. The reversal of 561280665 is 566082165.

561280665 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (561280663) and next prime (561280667).

It is not a de Polignac number, because 561280665 - 2¹ = 561280663 is a prime.

It is a super-3 number, since 3×561280665³ (a number of 27 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (561280663) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 216346 + ... + 218924.

It is an arithmetic number, because the mean of its divisors is an integer number (30650400).

Almost surely, 2^561280665 is an apocalyptic number.

561280665 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

It is an amenable number.

561280665 is a deficient number, since it is larger than the sum of its proper divisors (419532135).

561280665 is a wasteful number, since it uses less digits than its factorization.

561280665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3917.

The product of its (nonzero) digits is 86400, while the sum is 39.

The square root of 561280665 is about 23691.3626665922. The cubic root of 561280665 is about 824.8849132392.

The spelling of 561280665 in words is "five hundred sixty-one million, two hundred eighty thousand, six hundred sixty-five".