163553643 has 36 divisors (see below), whose sum is σ = 262420704. Its totient is φ = 98076000.

The previous prime is 163553623. The next prime is 163553657. The reversal of 163553643 is 346355361.

163553643 is a `hidden beast` number, since 1 + 6 + 3 + 5 + 5 + 3 + 643 = 666.

It is not a de Polignac number, because 163553643 - 2¹³ = 163545451 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 163553598 and 163553607.

It is not an unprimeable number, because it can be changed into a prime (163553603) 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 35 ways as a sum of consecutive naturals, for example, 109246 + ... + 110732.

It is an arithmetic number, because the mean of its divisors is an integer number (7289464).

Almost surely, 2^163553643 is an apocalyptic number.

163553643 is a deficient number, since it is larger than the sum of its proper divisors (98867061).

163553643 is a wasteful number, since it uses less digits than its factorization.

163553643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1616 (or 1602 counting only the distinct ones).

The product of its digits is 97200, while the sum is 36.

The square root of 163553643 is about 12788.8092878110. The cubic root of 163553643 is about 546.8733256351.

It can be divided in two parts, 1635 and 53643, that added together give a triangular number (55278 = T₃₃₂).

The spelling of 163553643 in words is "one hundred sixty-three million, five hundred fifty-three thousand, six hundred forty-three".