857344009 has 2 divisors, whose sum is σ = 857344010. Its totient is φ = 857344008.

The previous prime is 857343947. The next prime is 857344013. The reversal of 857344009 is 900443758.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 850305600 + 7038409 = 29160^2 + 2653^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-857344009 is a prime.

It is a super-4 number, since 4×857344009⁴ (a number of 37 digits) contains 4444 as substring.

It is not a weakly prime, because it can be changed into another prime (857344039) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 428672004 + 428672005.

It is an arithmetic number, because the mean of its divisors is an integer number (428672005).

Almost surely, 2^857344009 is an apocalyptic number.

It is an amenable number.

857344009 is a deficient number, since it is larger than the sum of its proper divisors (1).

857344009 is an equidigital number, since it uses as much as digits as its factorization.

857344009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 120960, while the sum is 40.

The square root of 857344009 is about 29280.4373088928. The cubic root of 857344009 is about 949.9885535094.

The spelling of 857344009 in words is "eight hundred fifty-seven million, three hundred forty-four thousand, nine".