77809826457 has 72 divisors (see below), whose sum is σ = 125414813160. Its totient is φ = 46445414400.

The previous prime is 77809826443. The next prime is 77809826467. The reversal of 77809826457 is 75462890877.

77809826457 is a `hidden beast` number, since 7 + 78 + 0 + 98 + 26 + 457 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 12097580121 + 65712246336 = 109989^2 + 256344^2 .

It is not a de Polignac number, because 77809826457 - 2¹⁰ = 77809825433 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 77809826394 and 77809826403.

It is not an unprimeable number, because it can be changed into a prime (77809826467) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 27233373 + ... + 27236229.

It is an arithmetic number, because the mean of its divisors is an integer number (1741872405).

Almost surely, 2^77809826457 is an apocalyptic number.

It is an amenable number.

77809826457 is a deficient number, since it is larger than the sum of its proper divisors (47604986703).

77809826457 is a wasteful number, since it uses less digits than its factorization.

77809826457 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3255 (or 3241 counting only the distinct ones).

The product of its (nonzero) digits is 47416320, while the sum is 63.

The spelling of 77809826457 in words is "seventy-seven billion, eight hundred nine million, eight hundred twenty-six thousand, four hundred fifty-seven".