161777887 has 2 divisors, whose sum is σ = 161777888. Its totient is φ = 161777886.

The previous prime is 161777879. The next prime is 161777947. The reversal of 161777887 is 788777161.

It is a happy number.

161777887 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 161777887 - 2³ = 161777879 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161777827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80888943 + 80888944.

It is an arithmetic number, because the mean of its divisors is an integer number (80888944).

Almost surely, 2^161777887 is an apocalyptic number.

161777887 is a deficient number, since it is larger than the sum of its proper divisors (1).

161777887 is an equidigital number, since it uses as much as digits as its factorization.

161777887 is an evil number, because the sum of its binary digits is even.

The product of its digits is 921984, while the sum is 52.

The square root of 161777887 is about 12719.1936458252. The cubic root of 161777887 is about 544.8869243287.

The spelling of 161777887 in words is "one hundred sixty-one million, seven hundred seventy-seven thousand, eight hundred eighty-seven".