77393570809 has 27 divisors (see below), whose sum is σ = 82149069639. Its totient is φ = 72909869760.

The previous prime is 77393570801. The next prime is 77393570819. The reversal of 77393570809 is 90807539377.

The square root of 77393570809 is 278197.

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

It can be written as a sum of positive squares in 13 ways, for example, as 67873275625 + 9520295184 = 260525^2 + 97572^2 .

It is not a de Polignac number, because 77393570809 - 2³ = 77393570801 is a prime.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77393570801) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 427588699 + ... + 427588879.

Almost surely, 2^77393570809 is an apocalyptic number.

77393570809 is the 278197-th square number.

77393570809 is the 139099-th centered octagonal number.

It is an amenable number.

77393570809 is a deficient number, since it is larger than the sum of its proper divisors (4755498830).

77393570809 is an frugal number, since it uses more digits than its factorization.

77393570809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 526 (or 263 counting only the distinct ones).

The product of its (nonzero) digits is 10001880, while the sum is 58.

The spelling of 77393570809 in words is "seventy-seven billion, three hundred ninety-three million, five hundred seventy thousand, eight hundred nine".