77261406161 has 4 divisors (see below), whose sum is σ = 77361876900. Its totient is φ = 77160935424.

The previous prime is 77261406139. The next prime is 77261406199. The reversal of 77261406161 is 16160416277.

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 60236375761 + 17025030400 = 245431^2 + 130480^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77261406161 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77261405161) 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, 50234216 + ... + 50235753.

It is an arithmetic number, because the mean of its divisors is an integer number (19340469225).

Almost surely, 2^77261406161 is an apocalyptic number.

It is an amenable number.

77261406161 is a deficient number, since it is larger than the sum of its proper divisors (100470739).

77261406161 is a wasteful number, since it uses less digits than its factorization.

77261406161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 100470738.

The product of its (nonzero) digits is 84672, while the sum is 41.

The spelling of 77261406161 in words is "seventy-seven billion, two hundred sixty-one million, four hundred six thousand, one hundred sixty-one".