77721741658 has 64 divisors (see below), whose sum is σ = 135672122880. Its totient is φ = 33020481600.

The previous prime is 77721741649. The next prime is 77721741661. The reversal of 77721741658 is 85614712777.

It is a junction number, because it is equal to n+sod(n) for n = 77721741599 and 77721741608.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 42915573 + ... + 42917383.

It is an arithmetic number, because the mean of its divisors is an integer number (2119876920).

Almost surely, 2^77721741658 is an apocalyptic number.

77721741658 is a deficient number, since it is larger than the sum of its proper divisors (57950381222).

77721741658 is a wasteful number, since it uses less digits than its factorization.

77721741658 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3163.

The product of its digits is 4609920, while the sum is 55.

The spelling of 77721741658 in words is "seventy-seven billion, seven hundred twenty-one million, seven hundred forty-one thousand, six hundred fifty-eight".