616555649 has 2 divisors, whose sum is σ = 616555650. Its totient is φ = 616555648.

The previous prime is 616555637. The next prime is 616555651. The reversal of 616555649 is 946555616.

616555649 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 410346049 + 206209600 = 20257^2 + 14360^2 .

It is a cyclic number.

It is not a de Polignac number, because 616555649 - 2⁸ = 616555393 is a prime.

It is a super-2 number, since 2×616555649² = 760281736627622402, which contains 22 as substring.

Together with 616555651, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (616555619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 308277824 + 308277825.

It is an arithmetic number, because the mean of its divisors is an integer number (308277825).

Almost surely, 2^616555649 is an apocalyptic number.

It is an amenable number.

616555649 is a deficient number, since it is larger than the sum of its proper divisors (1).

616555649 is an equidigital number, since it uses as much as digits as its factorization.

616555649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 972000, while the sum is 47.

The square root of 616555649 is about 24830.5386369285. The cubic root of 616555649 is about 851.1199304602.

The spelling of 616555649 in words is "six hundred sixteen million, five hundred fifty-five thousand, six hundred forty-nine".