103505821 has 4 divisors (see below), whose sum is σ = 105050752. Its totient is φ = 101960892.

The previous prime is 103505813. The next prime is 103505827. The reversal of 103505821 is 128505301.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 128505301 = 23 ⋅5587187.

It is a cyclic number.

It is not a de Polignac number, because 103505821 - 2³ = 103505813 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (103505827) 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 3 ways as a sum of consecutive naturals, for example, 772365 + ... + 772498.

It is an arithmetic number, because the mean of its divisors is an integer number (26262688).

Almost surely, 2^103505821 is an apocalyptic number.

It is an amenable number.

103505821 is a deficient number, since it is larger than the sum of its proper divisors (1544931).

103505821 is an equidigital number, since it uses as much as digits as its factorization.

103505821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1544930.

The product of its (nonzero) digits is 1200, while the sum is 25.

The square root of 103505821 is about 10173.7810572078. The cubic root of 103505821 is about 469.5208955138.

The spelling of 103505821 in words is "one hundred three million, five hundred five thousand, eight hundred twenty-one".