161641044 has 18 divisors (see below), whose sum is σ = 408592730. Its totient is φ = 53880336.

The previous prime is 161641027. The next prime is 161641057. The reversal of 161641044 is 440146161.

161641044 is a `hidden beast` number, since 1 + 616 + 4 + 1 + 0 + 44 = 666.

It can be written as a sum of positive squares in only one way, i.e., 133125444 + 28515600 = 11538^2 + 5340^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a super-2 number, since 2×161641044² = 52255654210819872, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 161640999 and 161641017.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2244979 + ... + 2245050.

Almost surely, 2^161641044 is an apocalyptic number.

It is an amenable number.

161641044 is an abundant number, since it is smaller than the sum of its proper divisors (246951686).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161641044 is a wasteful number, since it uses less digits than its factorization.

161641044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4490039 (or 4490034 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

The square root of 161641044 is about 12713.8131180225. The cubic root of 161641044 is about 544.7332465580.

The spelling of 161641044 in words is "one hundred sixty-one million, six hundred forty-one thousand, forty-four".