247042309 has 2 divisors, whose sum is σ = 247042310. Its totient is φ = 247042308.

The previous prime is 247042291. The next prime is 247042319. The reversal of 247042309 is 903240742.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 216737284 + 30305025 = 14722^2 + 5505^2 .

It is a cyclic number.

It is not a de Polignac number, because 247042309 - 2¹⁷ = 246911237 is a prime.

It is a super-2 number, since 2×247042309² = 122059804872102962, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (247042319) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 123521154 + 123521155.

It is an arithmetic number, because the mean of its divisors is an integer number (123521155).

Almost surely, 2^247042309 is an apocalyptic number.

It is an amenable number.

247042309 is a deficient number, since it is larger than the sum of its proper divisors (1).

247042309 is an equidigital number, since it uses as much as digits as its factorization.

247042309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12096, while the sum is 31.

The square root of 247042309 is about 15717.5796164677. The cubic root of 247042309 is about 627.4663582013.

The spelling of 247042309 in words is "two hundred forty-seven million, forty-two thousand, three hundred nine".