77777897489 has 4 divisors (see below), whose sum is σ = 77782959156. Its totient is φ = 77772835824.

The previous prime is 77777897479. The next prime is 77777897503. The reversal of 77777897489 is 98479877777.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 27246454225 + 50531443264 = 165065^2 + 224792^2 .

It is a cyclic number.

It is not a de Polignac number, because 77777897489 - 2¹⁶ = 77777831953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77777897479) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2507714 + ... + 2538539.

It is an arithmetic number, because the mean of its divisors is an integer number (19445739789).

Almost surely, 2^77777897489 is an apocalyptic number.

It is an amenable number.

77777897489 is a deficient number, since it is larger than the sum of its proper divisors (5061667).

77777897489 is a wasteful number, since it uses less digits than its factorization.

77777897489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5061666.

The product of its digits is 2439569664, while the sum is 80.

The spelling of 77777897489 in words is "seventy-seven billion, seven hundred seventy-seven million, eight hundred ninety-seven thousand, four hundred eighty-nine".