840234709 has 2 divisors, whose sum is σ = 840234710. Its totient is φ = 840234708.

The previous prime is 840234697. The next prime is 840234713. The reversal of 840234709 is 907432048.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 515153809 + 325080900 = 22697^2 + 18030^2 .

It is a cyclic number.

It is not a de Polignac number, because 840234709 - 2¹¹ = 840232661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (840232709) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 420117354 + 420117355.

It is an arithmetic number, because the mean of its divisors is an integer number (420117355).

Almost surely, 2^840234709 is an apocalyptic number.

It is an amenable number.

840234709 is a deficient number, since it is larger than the sum of its proper divisors (1).

840234709 is an equidigital number, since it uses as much as digits as its factorization.

840234709 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48384, while the sum is 37.

The square root of 840234709 is about 28986.8023245062. The cubic root of 840234709 is about 943.6266676603.

The spelling of 840234709 in words is "eight hundred forty million, two hundred thirty-four thousand, seven hundred nine".