561503531 has 8 divisors (see below), whose sum is σ = 595848960. Its totient is φ = 527985832.

The previous prime is 561503513. The next prime is 561503563. The reversal of 561503531 is 135305165.

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 561503531 - 2¹⁰ = 561502507 is a prime.

It is a super-2 number, since 2×561503531² = 630572430650935922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 561503494 and 561503503.

It is not an unprimeable number, because it can be changed into a prime (561505531) 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, 205535 + ... + 208248.

It is an arithmetic number, because the mean of its divisors is an integer number (74481120).

Almost surely, 2^561503531 is an apocalyptic number.

561503531 is a deficient number, since it is larger than the sum of its proper divisors (34345429).

561503531 is a wasteful number, since it uses less digits than its factorization.

561503531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 413865.

The product of its (nonzero) digits is 6750, while the sum is 29.

The square root of 561503531 is about 23696.0657283018. The cubic root of 561503531 is about 824.9940769700.

Adding to 561503531 its reverse (135305165), we get a palindrome (696808696).

The spelling of 561503531 in words is "five hundred sixty-one million, five hundred three thousand, five hundred thirty-one".