77753418649 has 3 divisors (see below), whose sum is σ = 77753697493. Its totient is φ = 77753139806.

The previous prime is 77753418641. The next prime is 77753418731. The reversal of 77753418649 is 94681435777.

The square root of 77753418649 is 278843.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 94681435777 = 409 ⋅231494953.

It is not a de Polignac number, because 77753418649 - 2³ = 77753418641 is a prime.

It is a super-2 number, since 2×77753418649² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77753418641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 139422 + ... + 418264.

Almost surely, 2^77753418649 is an apocalyptic number.

77753418649 is the 278843-rd square number.

77753418649 is the 139422-nd centered octagonal number.

It is an amenable number.

77753418649 is a deficient number, since it is larger than the sum of its proper divisors (278844).

77753418649 is an frugal number, since it uses more digits than its factorization.

77753418649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 557686 (or 278843 counting only the distinct ones).

The product of its digits is 35562240, while the sum is 61.

The spelling of 77753418649 in words is "seventy-seven billion, seven hundred fifty-three million, four hundred eighteen thousand, six hundred forty-nine".