563638981 has 4 divisors (see below), whose sum is σ = 564076864. Its totient is φ = 563201100.

The previous prime is 563638939. The next prime is 563638987. The reversal of 563638981 is 189836365.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 563638981 - 2⁹ = 563638469 is a prime.

It is a super-2 number, since 2×563638981² = 635377801805436722, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (563638987) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 217005 + ... + 219586.

It is an arithmetic number, because the mean of its divisors is an integer number (141019216).

Almost surely, 2^563638981 is an apocalyptic number.

It is an amenable number.

563638981 is a deficient number, since it is larger than the sum of its proper divisors (437883).

563638981 is a wasteful number, since it uses less digits than its factorization.

563638981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 437882.

The product of its digits is 933120, while the sum is 49.

The square root of 563638981 is about 23741.0821362464. The cubic root of 563638981 is about 826.0385969453.

The spelling of 563638981 in words is "five hundred sixty-three million, six hundred thirty-eight thousand, nine hundred eighty-one".