531265561 has 2 divisors, whose sum is σ = 531265562. Its totient is φ = 531265560.

The previous prime is 531265543. The next prime is 531265571. The reversal of 531265561 is 165562135.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 507645961 + 23619600 = 22531^2 + 4860^2 .

It is a cyclic number.

It is not a de Polignac number, because 531265561 - 2⁷ = 531265433 is a prime.

It is not a weakly prime, because it can be changed into another prime (531265571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 265632780 + 265632781.

It is an arithmetic number, because the mean of its divisors is an integer number (265632781).

Almost surely, 2^531265561 is an apocalyptic number.

It is an amenable number.

531265561 is a deficient number, since it is larger than the sum of its proper divisors (1).

531265561 is an equidigital number, since it uses as much as digits as its factorization.

531265561 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 531265561 is about 23049.1987062457. The cubic root of 531265561 is about 809.9108579440.

The spelling of 531265561 in words is "five hundred thirty-one million, two hundred sixty-five thousand, five hundred sixty-one".