77687338408 has 16 divisors (see below), whose sum is σ = 145681888500. Its totient is φ = 38838834816.

The previous prime is 77687338403. The next prime is 77687338423. The reversal of 77687338408 is 80483378677.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 70287553924 + 7399784484 = 265118^2 + 86022^2 .

It is a super-2 number, since 2×77687338408² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (77687338403) 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, 535543 + ... + 664966.

Almost surely, 2^77687338408 is an apocalyptic number.

It is an amenable number.

77687338408 is a deficient number, since it is larger than the sum of its proper divisors (67994550092).

77687338408 is a wasteful number, since it uses less digits than its factorization.

77687338408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1208604 (or 1208600 counting only the distinct ones).

The product of its (nonzero) digits is 37933056, while the sum is 61.

The spelling of 77687338408 in words is "seventy-seven billion, six hundred eighty-seven million, three hundred thirty-eight thousand, four hundred eight".