163781449 has 12 divisors (see below), whose sum is σ = 179358300. Its totient is φ = 149470464.

The previous prime is 163781441. The next prime is 163781467. The reversal of 163781449 is 944187361.

It can be written as a sum of positive squares in 6 ways, for example, as 94225849 + 69555600 = 9707^2 + 8340^2 .

It is not a de Polignac number, because 163781449 - 2³ = 163781441 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (163781441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9597 + ... + 20485.

It is an arithmetic number, because the mean of its divisors is an integer number (14946525).

Almost surely, 2^163781449 is an apocalyptic number.

It is an amenable number.

163781449 is a deficient number, since it is larger than the sum of its proper divisors (15576851).

163781449 is a wasteful number, since it uses less digits than its factorization.

163781449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11004 (or 10991 counting only the distinct ones).

The product of its digits is 145152, while the sum is 43.

The square root of 163781449 is about 12797.7126471882. The cubic root of 163781449 is about 547.1271123567.

The spelling of 163781449 in words is "one hundred sixty-three million, seven hundred eighty-one thousand, four hundred forty-nine".