3121403 has 4 divisors (see below), whose sum is σ = 3127080. Its totient is φ = 3115728.

The previous prime is 3121379. The next prime is 3121409. The reversal of 3121403 is 3041213.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3041213 = 7 ⋅434459.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3121403 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3121409) 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, 1913 + ... + 3146.

It is an arithmetic number, because the mean of its divisors is an integer number (781770).

Almost surely, 2^3121403 is an apocalyptic number.

3121403 is a deficient number, since it is larger than the sum of its proper divisors (5677).

3121403 is an equidigital number, since it uses as much as digits as its factorization.

3121403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5676.

The product of its (nonzero) digits is 72, while the sum is 14.

The square root of 3121403 is about 1766.7492747982. The cubic root of 3121403 is about 146.1447710183.

Adding to 3121403 its reverse (3041213), we get a palindrome (6162616).

The spelling of 3121403 in words is "three million, one hundred twenty-one thousand, four hundred three".