617721347 has 2 divisors, whose sum is σ = 617721348. Its totient is φ = 617721346.

The previous prime is 617721343. The next prime is 617721383. The reversal of 617721347 is 743127716.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 617721347 - 2² = 617721343 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 617721347.

It is not a weakly prime, because it can be changed into another prime (617721343) 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, 308860673 + 308860674.

It is an arithmetic number, because the mean of its divisors is an integer number (308860674).

Almost surely, 2^617721347 is an apocalyptic number.

617721347 is a deficient number, since it is larger than the sum of its proper divisors (1).

617721347 is an equidigital number, since it uses as much as digits as its factorization.

617721347 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 49392, while the sum is 38.

The square root of 617721347 is about 24854.0006236421. Note that the first 3 decimals coincide. The cubic root of 617721347 is about 851.6559859840.

The spelling of 617721347 in words is "six hundred seventeen million, seven hundred twenty-one thousand, three hundred forty-seven".