616769561 has 2 divisors, whose sum is σ = 616769562. Its totient is φ = 616769560.

The previous prime is 616769513. The next prime is 616769567. The reversal of 616769561 is 165967616.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 405619600 + 211149961 = 20140^2 + 14531^2 .

It is a cyclic number.

It is not a de Polignac number, because 616769561 - 2⁶ = 616769497 is a prime.

It is a super-2 number, since 2×616769561² = 760809382752265442, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (616769567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 308384780 + 308384781.

It is an arithmetic number, because the mean of its divisors is an integer number (308384781).

Almost surely, 2^616769561 is an apocalyptic number.

It is an amenable number.

616769561 is a deficient number, since it is larger than the sum of its proper divisors (1).

616769561 is an equidigital number, since it uses as much as digits as its factorization.

616769561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 408240, while the sum is 47.

The square root of 616769561 is about 24834.8457011514. The cubic root of 616769561 is about 851.2183501867.

The spelling of 616769561 in words is "six hundred sixteen million, seven hundred sixty-nine thousand, five hundred sixty-one".