103561681 has 4 divisors (see below), whose sum is σ = 103888692. Its totient is φ = 103234672.

The previous prime is 103561651. The next prime is 103561687. The reversal of 103561681 is 186165301.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 186165301 = 7 ⋅26595043.

It can be written as a sum of positive squares in 2 ways, for example, as 29257281 + 74304400 = 5409^2 + 8620^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-103561681 is a prime.

It is a super-3 number, since 3×103561681³ (a number of 25 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (103561687) 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 3 ways as a sum of consecutive naturals, for example, 163030 + ... + 163663.

It is an arithmetic number, because the mean of its divisors is an integer number (25972173).

Almost surely, 2^103561681 is an apocalyptic number.

It is an amenable number.

103561681 is a deficient number, since it is larger than the sum of its proper divisors (327011).

103561681 is an equidigital number, since it uses as much as digits as its factorization.

103561681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 327010.

The product of its (nonzero) digits is 4320, while the sum is 31.

The square root of 103561681 is about 10176.5259789380. The cubic root of 103561681 is about 469.6053439704.

The spelling of 103561681 in words is "one hundred three million, five hundred sixty-one thousand, six hundred eighty-one".