561155263 has 2 divisors, whose sum is σ = 561155264. Its totient is φ = 561155262.

The previous prime is 561155201. The next prime is 561155297. The reversal of 561155263 is 362551165.

It is an a-pointer prime, because the next prime (561155297) can be obtained adding 561155263 to its sum of digits (34).

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-561155263 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (561155563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 280577631 + 280577632.

It is an arithmetic number, because the mean of its divisors is an integer number (280577632).

Almost surely, 2^561155263 is an apocalyptic number.

561155263 is a deficient number, since it is larger than the sum of its proper divisors (1).

561155263 is an equidigital number, since it uses as much as digits as its factorization.

561155263 is an evil number, because the sum of its binary digits is even.

The product of its digits is 27000, while the sum is 34.

The square root of 561155263 is about 23688.7159424060. The cubic root of 561155263 is about 824.8234764043.

The spelling of 561155263 in words is "five hundred sixty-one million, one hundred fifty-five thousand, two hundred sixty-three".