247639399156817 has 2 divisors, whose sum is σ = 247639399156818. Its totient is φ = 247639399156816.

The previous prime is 247639399156777. The next prime is 247639399156837. The reversal of 247639399156817 is 718651993936742.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 164968952512576 + 82670446644241 = 12844024^2 + 9092329^2 .

It is a cyclic number.

It is not a de Polignac number, because 247639399156817 - 2¹² = 247639399152721 is a prime.

It is a super-2 number, since 2×247639399156817² (a number of 30 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (247639399156837) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 123819699578408 + 123819699578409.

It is an arithmetic number, because the mean of its divisors is an integer number (123819699578409).

Almost surely, 2^{247639399156817} is an apocalyptic number.

It is an amenable number.

247639399156817 is a deficient number, since it is larger than the sum of its proper divisors (1).

247639399156817 is an equidigital number, since it uses as much as digits as its factorization.

247639399156817 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3703553280, while the sum is 80.

The spelling of 247639399156817 in words is "two hundred forty-seven trillion, six hundred thirty-nine billion, three hundred ninety-nine million, one hundred fifty-six thousand, eight hundred seventeen".