561673021 has 12 divisors (see below), whose sum is σ = 695089632. Its totient is φ = 444399696.

The previous prime is 561673001. The next prime is 561673027. The reversal of 561673021 is 120376165.

It is not a de Polignac number, because 561673021 - 2⁵ = 561672989 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 (561673027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 236211 + ... + 238576.

It is an arithmetic number, because the mean of its divisors is an integer number (57924136).

Almost surely, 2^561673021 is an apocalyptic number.

It is an amenable number.

561673021 is a deficient number, since it is larger than the sum of its proper divisors (133416611).

561673021 is a wasteful number, since it uses less digits than its factorization.

561673021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 474820 (or 474807 counting only the distinct ones).

The product of its (nonzero) digits is 7560, while the sum is 31.

The square root of 561673021 is about 23699.6417905419. The cubic root of 561673021 is about 825.0770768514.

The spelling of 561673021 in words is "five hundred sixty-one million, six hundred seventy-three thousand, twenty-one".