561649511 has 2 divisors, whose sum is σ = 561649512. Its totient is φ = 561649510.

The previous prime is 561649507. The next prime is 561649549. The reversal of 561649511 is 115946165.

It is an a-pointer prime, because the next prime (561649549) can be obtained adding 561649511 to its sum of digits (38).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 561649511 - 2² = 561649507 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (561649591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 280824755 + 280824756.

It is an arithmetic number, because the mean of its divisors is an integer number (280824756).

Almost surely, 2^561649511 is an apocalyptic number.

561649511 is a deficient number, since it is larger than the sum of its proper divisors (1).

561649511 is an equidigital number, since it uses as much as digits as its factorization.

561649511 is an evil number, because the sum of its binary digits is even.

The product of its digits is 32400, while the sum is 38.

The square root of 561649511 is about 23699.1457862936. The cubic root of 561649511 is about 825.0655649147.

The spelling of 561649511 in words is "five hundred sixty-one million, six hundred forty-nine thousand, five hundred eleven".