77650409930809 has 27 divisors (see below), whose sum is σ = 80332725939309. Its totient is φ = 75056639767200.

The previous prime is 77650409930801. The next prime is 77650409930833. The reversal of 77650409930809 is 90803990405677.

The square root of 77650409930809 is 8811947.

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

It can be written as a sum of positive squares in 4 ways, for example, as 71378791268409 + 6271618662400 = 8448597^2 + 2504320^2 .

It is not a de Polignac number, because 77650409930809 - 2³ = 77650409930801 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77650409930801) 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, 38270284807 + ... + 38270286835.

Almost surely, 2^{77650409930809} is an apocalyptic number.

77650409930809 is the 8811947-th square number.

77650409930809 is the 4405974-th centered octagonal number.

It is an amenable number.

77650409930809 is a deficient number, since it is larger than the sum of its proper divisors (2682316008500).

77650409930809 is an frugal number, since it uses more digits than its factorization.

77650409930809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4346 (or 2173 counting only the distinct ones).

The product of its (nonzero) digits is 102876480, while the sum is 67.

The spelling of 77650409930809 in words is "seventy-seven trillion, six hundred fifty billion, four hundred nine million, nine hundred thirty thousand, eight hundred nine".