161409396779 has 2 divisors, whose sum is σ = 161409396780. Its totient is φ = 161409396778.

The previous prime is 161409396769. The next prime is 161409396793. The reversal of 161409396779 is 977693904161.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 161409396779 - 2⁸ = 161409396523 is a prime.

It is not a weakly prime, because it can be changed into another prime (161409396769) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80704698389 + 80704698390.

It is an arithmetic number, because the mean of its divisors is an integer number (80704698390).

Almost surely, 2^161409396779 is an apocalyptic number.

161409396779 is a deficient number, since it is larger than the sum of its proper divisors (1).

161409396779 is an equidigital number, since it uses as much as digits as its factorization.

161409396779 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15431472, while the sum is 62.

The spelling of 161409396779 in words is "one hundred sixty-one billion, four hundred nine million, three hundred ninety-six thousand, seven hundred seventy-nine".