103818521 has 4 divisors (see below), whose sum is σ = 107398500. Its totient is φ = 100238544.

The previous prime is 103818503. The next prime is 103818529. The reversal of 103818521 is 125818301.

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

It can be written as a sum of positive squares in 2 ways, for example, as 81360400 + 22458121 = 9020^2 + 4739^2 .

It is a cyclic number.

It is not a de Polignac number, because 103818521 - 2¹⁴ = 103802137 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29), and also a Moran number because the ratio is a prime number: 3579949 = 103818521 / (1 + 0 + 3 + 8 + 1 + 8 + 5 + 2 + 1).

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (103818529) 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, 1789946 + ... + 1790003.

It is an arithmetic number, because the mean of its divisors is an integer number (26849625).

Almost surely, 2^103818521 is an apocalyptic number.

It is an amenable number.

103818521 is a deficient number, since it is larger than the sum of its proper divisors (3579979).

103818521 is an equidigital number, since it uses as much as digits as its factorization.

103818521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3579978.

The product of its (nonzero) digits is 1920, while the sum is 29.

The square root of 103818521 is about 10189.1374021553. The cubic root of 103818521 is about 469.9932411885.

The spelling of 103818521 in words is "one hundred three million, eight hundred eighteen thousand, five hundred twenty-one".