77961096181 has 4 divisors (see below), whose sum is σ = 78161510700. Its totient is φ = 77760681664.

The previous prime is 77961096179. The next prime is 77961096211. The reversal of 77961096181 is 18169016977.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 25270189156 + 52690907025 = 158966^2 + 229545^2 .

It is a cyclic number.

It is not a de Polignac number, because 77961096181 - 2¹ = 77961096179 is a prime.

It is a super-2 number, since 2×77961096181² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77961096151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 100206676 + ... + 100207453.

It is an arithmetic number, because the mean of its divisors is an integer number (19540377675).

Almost surely, 2^77961096181 is an apocalyptic number.

It is an amenable number.

77961096181 is a deficient number, since it is larger than the sum of its proper divisors (200414519).

77961096181 is a wasteful number, since it uses less digits than its factorization.

77961096181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200414518.

The product of its (nonzero) digits is 1143072, while the sum is 55.

The spelling of 77961096181 in words is "seventy-seven billion, nine hundred sixty-one million, ninety-six thousand, one hundred eighty-one".