161555155 has 8 divisors (see below), whose sum is σ = 194126832. Its totient is φ = 129070368.

The previous prime is 161555123. The next prime is 161555179. The reversal of 161555155 is 551555161.

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 161555155 - 2⁵ = 161555123 is a prime.

It is a super-2 number, since 2×161555155² = 52200136214148050, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 161555155.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17557 + ... + 25126.

It is an arithmetic number, because the mean of its divisors is an integer number (24265854).

Almost surely, 2^161555155 is an apocalyptic number.

161555155 is a deficient number, since it is larger than the sum of its proper divisors (32571677).

161555155 is an equidigital number, since it uses as much as digits as its factorization.

161555155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43445.

The product of its digits is 18750, while the sum is 34.

The square root of 161555155 is about 12710.4348863444. The cubic root of 161555155 is about 544.6367469687.

The spelling of 161555155 in words is "one hundred sixty-one million, five hundred fifty-five thousand, one hundred fifty-five".