161555519 has 8 divisors (see below), whose sum is σ = 168791040. Its totient is φ = 154337656.

The previous prime is 161555509. The next prime is 161555521. The reversal of 161555519 is 915555161.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 161555519 - 2⁴ = 161555503 is a prime.

It is a super-2 number, since 2×161555519² = 52200371438718722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161555509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16442 + ... + 24360.

It is an arithmetic number, because the mean of its divisors is an integer number (21098880).

Almost surely, 2^161555519 is an apocalyptic number.

161555519 is a deficient number, since it is larger than the sum of its proper divisors (7235521).

161555519 is an equidigital number, since it uses as much as digits as its factorization.

161555519 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8829.

The product of its digits is 33750, while the sum is 38.

The square root of 161555519 is about 12710.4492052799. The cubic root of 161555519 is about 544.6371560089.

The spelling of 161555519 in words is "one hundred sixty-one million, five hundred fifty-five thousand, five hundred nineteen".