161887520887 has 2 divisors, whose sum is σ = 161887520888. Its totient is φ = 161887520886.

The previous prime is 161887520869. The next prime is 161887520909. The reversal of 161887520887 is 788025788161.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161887520887 is a prime.

It is a super-2 number, since 2×161887520887² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161887520867) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80943760443 + 80943760444.

It is an arithmetic number, because the mean of its divisors is an integer number (80943760444).

Almost surely, 2^161887520887 is an apocalyptic number.

161887520887 is a deficient number, since it is larger than the sum of its proper divisors (1).

161887520887 is an equidigital number, since it uses as much as digits as its factorization.

161887520887 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12042240, while the sum is 61.

The spelling of 161887520887 in words is "one hundred sixty-one billion, eight hundred eighty-seven million, five hundred twenty thousand, eight hundred eighty-seven".