161641783 has 4 divisors (see below), whose sum is σ = 163856128. Its totient is φ = 159427440.

The previous prime is 161641771. The next prime is 161641811. The reversal of 161641783 is 387146161.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 161641783 - 2¹⁷ = 161510711 is a prime.

It is a super-2 number, since 2×161641783² = 52256132022838178, 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 (161641283) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1107063 + ... + 1107208.

It is an arithmetic number, because the mean of its divisors is an integer number (40964032).

Almost surely, 2^161641783 is an apocalyptic number.

161641783 is a deficient number, since it is larger than the sum of its proper divisors (2214345).

161641783 is an equidigital number, since it uses as much as digits as its factorization.

161641783 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2214344.

The product of its digits is 24192, while the sum is 37.

The square root of 161641783 is about 12713.8421808673. The cubic root of 161641783 is about 544.7340767045.

The spelling of 161641783 in words is "one hundred sixty-one million, six hundred forty-one thousand, seven hundred eighty-three".