3103721 has 4 divisors (see below), whose sum is σ = 3107412. Its totient is φ = 3100032.

The previous prime is 3103693. The next prime is 3103729. The reversal of 3103721 is 1273013.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 1690000 + 1413721 = 1300^2 + 1189^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3103721 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 3103721.

It is not an unprimeable number, because it can be changed into a prime (3103729) 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, 101 + ... + 2493.

It is an arithmetic number, because the mean of its divisors is an integer number (776853).

Almost surely, 2^3103721 is an apocalyptic number.

It is an amenable number.

3103721 is a deficient number, since it is larger than the sum of its proper divisors (3691).

3103721 is a wasteful number, since it uses less digits than its factorization.

3103721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3690.

The product of its (nonzero) digits is 126, while the sum is 17.

The square root of 3103721 is about 1761.7380622556. The cubic root of 3103721 is about 145.8682899240.

Adding to 3103721 its reverse (1273013), we get a palindrome (4376734).

The spelling of 3103721 in words is "three million, one hundred three thousand, seven hundred twenty-one".