261224647 has 2 divisors, whose sum is σ = 261224648. Its totient is φ = 261224646.

The previous prime is 261224641. The next prime is 261224657. The reversal of 261224647 is 746422162.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 261224647 - 2⁷ = 261224519 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261224641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130612323 + 130612324.

It is an arithmetic number, because the mean of its divisors is an integer number (130612324).

Almost surely, 2^261224647 is an apocalyptic number.

261224647 is a deficient number, since it is larger than the sum of its proper divisors (1).

261224647 is an equidigital number, since it uses as much as digits as its factorization.

261224647 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32256, while the sum is 34.

The square root of 261224647 is about 16162.4455760878. The cubic root of 261224647 is about 639.2509522795.

The spelling of 261224647 in words is "two hundred sixty-one million, two hundred twenty-four thousand, six hundred forty-seven".