775630649 has 2 divisors, whose sum is σ = 775630650. Its totient is φ = 775630648.

The previous prime is 775630619. The next prime is 775630651. The reversal of 775630649 is 946036577.

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., 684084025 + 91546624 = 26155^2 + 9568^2 .

It is an emirp because it is prime and its reverse (946036577) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 775630649 - 2⁸ = 775630393 is a prime.

It is a super-2 number, since 2×775630649² = 1203205807336322402, which contains 22 as substring.

Together with 775630651, 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 (775630619) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 387815324 + 387815325.

It is an arithmetic number, because the mean of its divisors is an integer number (387815325).

Almost surely, 2^775630649 is an apocalyptic number.

It is an amenable number.

775630649 is a deficient number, since it is larger than the sum of its proper divisors (1).

775630649 is an equidigital number, since it uses as much as digits as its factorization.

775630649 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 952560, while the sum is 47.

The square root of 775630649 is about 27850.1463012315. The cubic root of 775630649 is about 918.7943599974.

The spelling of 775630649 in words is "seven hundred seventy-five million, six hundred thirty thousand, six hundred forty-nine".