161090145 has 24 divisors (see below), whose sum is σ = 280139496. Its totient is φ = 85632768.

The previous prime is 161090143. The next prime is 161090173. The reversal of 161090145 is 541090161.

161090145 is a `hidden beast` number, since 1 + 610 + 9 + 0 + 1 + 45 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 2934369 + 158155776 = 1713^2 + 12576^2 .

It is not a de Polignac number, because 161090145 - 2¹ = 161090143 is a prime.

It is a super-2 number, since 2×161090145² = 51900069632242050, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (161090143) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8367 + ... + 19803.

It is an arithmetic number, because the mean of its divisors is an integer number (11672479).

Almost surely, 2^161090145 is an apocalyptic number.

161090145 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

161090145 is a deficient number, since it is larger than the sum of its proper divisors (119049351).

161090145 is a wasteful number, since it uses less digits than its factorization.

161090145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11761 (or 11758 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 27.

The square root of 161090145 is about 12692.1292539904. The cubic root of 161090145 is about 544.1136956438.

The spelling of 161090145 in words is "one hundred sixty-one million, ninety thousand, one hundred forty-five".