77553645328 has 40 divisors (see below), whose sum is σ = 155466310680. Its totient is φ = 37433733120.

The previous prime is 77553645313. The next prime is 77553645361. The reversal of 77553645328 is 82354635577.

It can be written as a sum of positive squares in 4 ways, for example, as 7840748304 + 69712897024 = 88548^2 + 264032^2 .

It is a super-2 number, since 2×77553645328² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4715776 + ... + 4732192.

It is an arithmetic number, because the mean of its divisors is an integer number (3886657767).

Almost surely, 2^77553645328 is an apocalyptic number.

It is an amenable number.

77553645328 is an abundant number, since it is smaller than the sum of its proper divisors (77912665352).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

77553645328 is a wasteful number, since it uses less digits than its factorization.

77553645328 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26635 (or 26629 counting only the distinct ones).

The product of its digits is 21168000, while the sum is 55.

The spelling of 77553645328 in words is "seventy-seven billion, five hundred fifty-three million, six hundred forty-five thousand, three hundred twenty-eight".