161987867 has 2 divisors, whose sum is σ = 161987868. Its totient is φ = 161987866.

The previous prime is 161987831. The next prime is 161987893. The reversal of 161987867 is 768789161.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 161987867 - 2¹² = 161983771 is a prime.

It is not a weakly prime, because it can be changed into another prime (161987807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80993933 + 80993934.

It is an arithmetic number, because the mean of its divisors is an integer number (80993934).

Almost surely, 2^161987867 is an apocalyptic number.

161987867 is a deficient number, since it is larger than the sum of its proper divisors (1).

161987867 is an equidigital number, since it uses as much as digits as its factorization.

161987867 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1016064, while the sum is 53.

The square root of 161987867 is about 12727.4454231790. The cubic root of 161987867 is about 545.1225681740.

The spelling of 161987867 in words is "one hundred sixty-one million, nine hundred eighty-seven thousand, eight hundred sixty-seven".