561919021 has 8 divisors (see below), whose sum is σ = 569462400. Its totient is φ = 554386560.

The previous prime is 561919019. The next prime is 561919097. The reversal of 561919021 is 120919165.

It is a happy number.

561919021 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 a cyclic number.

It is not a de Polignac number, because 561919021 - 2¹ = 561919019 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561919121) 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, 183261 + ... + 186301.

It is an arithmetic number, because the mean of its divisors is an integer number (71182800).

Almost surely, 2^561919021 is an apocalyptic number.

It is an amenable number.

561919021 is a deficient number, since it is larger than the sum of its proper divisors (7543379).

561919021 is a wasteful number, since it uses less digits than its factorization.

561919021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5459.

The product of its (nonzero) digits is 4860, while the sum is 34.

The square root of 561919021 is about 23704.8311742564. The cubic root of 561919021 is about 825.1975142640.

The spelling of 561919021 in words is "five hundred sixty-one million, nine hundred nineteen thousand, twenty-one".