163539681 has 8 divisors (see below), whose sum is σ = 221748960. Its totient is φ = 107178432.

The previous prime is 163539679. The next prime is 163539689. The reversal of 163539681 is 186935361.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 163539681 - 2¹ = 163539679 is a prime.

It is a super-4 number, since 4×163539681⁴ (a number of 34 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (163539689) 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 7 ways as a sum of consecutive naturals, for example, 461800 + ... + 462153.

It is an arithmetic number, because the mean of its divisors is an integer number (27718620).

Almost surely, 2^163539681 is an apocalyptic number.

It is an amenable number.

163539681 is a deficient number, since it is larger than the sum of its proper divisors (58209279).

163539681 is an equidigital number, since it uses as much as digits as its factorization.

163539681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 924015.

The product of its digits is 116640, while the sum is 42.

The square root of 163539681 is about 12788.2634082975. The cubic root of 163539681 is about 546.8577636407.

The spelling of 163539681 in words is "one hundred sixty-three million, five hundred thirty-nine thousand, six hundred eighty-one".