561610501 has 4 divisors (see below), whose sum is σ = 561955212. Its totient is φ = 561265792.

The previous prime is 561610459. The next prime is 561610519. The reversal of 561610501 is 105016165.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 192932100 + 368678401 = 13890^2 + 19201^2 .

It is a cyclic number.

It is not a de Polignac number, because 561610501 - 2¹⁹ = 561086213 is a prime.

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 (561610561) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 169900 + ... + 173173.

It is an arithmetic number, because the mean of its divisors is an integer number (140488803).

Almost surely, 2^561610501 is an apocalyptic number.

It is an amenable number.

561610501 is a deficient number, since it is larger than the sum of its proper divisors (344711).

561610501 is a wasteful number, since it uses less digits than its factorization.

561610501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 344710.

The product of its (nonzero) digits is 900, while the sum is 25.

The square root of 561610501 is about 23698.3227465574. The cubic root of 561610501 is about 825.0464625195.

Adding to 561610501 its reverse (105016165), we get a palindrome (666626666).

The spelling of 561610501 in words is "five hundred sixty-one million, six hundred ten thousand, five hundred one".