161201955 has 32 divisors (see below), whose sum is σ = 268607808. Its totient is φ = 82483200.

The previous prime is 161201951. The next prime is 161201977. The reversal of 161201955 is 559102161.

It is not a de Polignac number, because 161201955 - 2² = 161201951 is a prime.

It is not an unprimeable number, because it can be changed into a prime (161201951) 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 in 31 ways as a sum of consecutive naturals, for example, 35367 + ... + 39663.

It is an arithmetic number, because the mean of its divisors is an integer number (8393994).

Almost surely, 2^161201955 is an apocalyptic number.

161201955 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

161201955 is a deficient number, since it is larger than the sum of its proper divisors (107405853).

161201955 is a wasteful number, since it uses less digits than its factorization.

161201955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4407.

The product of its (nonzero) digits is 2700, while the sum is 30.

The square root of 161201955 is about 12696.5331882369. The cubic root of 161201955 is about 544.2395532960.

The spelling of 161201955 in words is "one hundred sixty-one million, two hundred one thousand, nine hundred fifty-five".