77801680161 has 12 divisors (see below), whose sum is σ = 112817485092. Its totient is φ = 51665965056.

The previous prime is 77801680141. The next prime is 77801680199. The reversal of 77801680161 is 16108610877.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 50931913761 + 26869766400 = 225681^2 + 163920^2 .

It is not a de Polignac number, because 77801680161 - 2⁶ = 77801680097 is a prime.

It is not an unprimeable number, because it can be changed into a prime (77801680141) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16816036 + ... + 16820661.

It is an arithmetic number, because the mean of its divisors is an integer number (9401457091).

Almost surely, 2^77801680161 is an apocalyptic number.

It is an amenable number.

77801680161 is a deficient number, since it is larger than the sum of its proper divisors (35015804931).

77801680161 is a wasteful number, since it uses less digits than its factorization.

77801680161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33636960 (or 33636957 counting only the distinct ones).

The product of its (nonzero) digits is 112896, while the sum is 45.

The spelling of 77801680161 in words is "seventy-seven billion, eight hundred one million, six hundred eighty thousand, one hundred sixty-one".