77928219149 has 6 divisors (see below), whose sum is σ = 85656637710. Its totient is φ = 70843835480.

The previous prime is 77928219137. The next prime is 77928219179. The reversal of 77928219149 is 94191282977.

It can be written as a sum of positive squares in only one way, i.e., 44838062500 + 33090156649 = 211750^2 + 181907^2 .

It is a de Polignac number, because none of the positive numbers 2^k-77928219149 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77928219179) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 322017314 + ... + 322017555.

It is an arithmetic number, because the mean of its divisors is an integer number (14276106285).

Almost surely, 2^77928219149 is an apocalyptic number.

It is an amenable number.

77928219149 is a deficient number, since it is larger than the sum of its proper divisors (7728418561).

77928219149 is a wasteful number, since it uses less digits than its factorization.

77928219149 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 644034891 (or 644034880 counting only the distinct ones).

The product of its digits is 4572288, while the sum is 59.

The spelling of 77928219149 in words is "seventy-seven billion, nine hundred twenty-eight million, two hundred nineteen thousand, one hundred forty-nine".