561661401 has 8 divisors (see below), whose sum is σ = 855865024. Its totient is φ = 320949360.

The previous prime is 561661393. The next prime is 561661417. The reversal of 561661401 is 104166165.

561661401 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 561661401 - 2³ = 561661393 is a prime.

It is not an unprimeable number, because it can be changed into a prime (561661301) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13372870 + ... + 13372911.

It is an arithmetic number, because the mean of its divisors is an integer number (106983128).

Almost surely, 2^561661401 is an apocalyptic number.

It is an amenable number.

561661401 is a deficient number, since it is larger than the sum of its proper divisors (294203623).

561661401 is a wasteful number, since it uses less digits than its factorization.

561661401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26745791.

The product of its (nonzero) digits is 4320, while the sum is 30.

The square root of 561661401 is about 23699.3966378893. The cubic root of 561661401 is about 825.0713870275.

The spelling of 561661401 in words is "five hundred sixty-one million, six hundred sixty-one thousand, four hundred one".