531065861 has 2 divisors, whose sum is σ = 531065862. Its totient is φ = 531065860.

The previous prime is 531065849. The next prime is 531065897. The reversal of 531065861 is 168560135.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 317730625 + 213335236 = 17825^2 + 14606^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-531065861 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 (531065461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 265532930 + 265532931.

It is an arithmetic number, because the mean of its divisors is an integer number (265532931).

Almost surely, 2^531065861 is an apocalyptic number.

It is an amenable number.

531065861 is a deficient number, since it is larger than the sum of its proper divisors (1).

531065861 is an equidigital number, since it uses as much as digits as its factorization.

531065861 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21600, while the sum is 35.

The square root of 531065861 is about 23044.8662612739. The cubic root of 531065861 is about 809.8093647800.

The spelling of 531065861 in words is "five hundred thirty-one million, sixty-five thousand, eight hundred sixty-one".