3121643 has 16 divisors (see below), whose sum is σ = 3840000. Its totient is φ = 2529576.

The previous prime is 3121633. The next prime is 3121663. The reversal of 3121643 is 3461213.

It is not a de Polignac number, because 3121643 - 2⁴ = 3121627 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3121603) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6278 + ... + 6756.

It is an arithmetic number, because the mean of its divisors is an integer number (240000).

Almost surely, 2^3121643 is an apocalyptic number.

3121643 is a deficient number, since it is larger than the sum of its proper divisors (718357).

3121643 is an equidigital number, since it uses as much as digits as its factorization.

3121643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 519 (or 505 counting only the distinct ones).

The product of its digits is 432, while the sum is 20.

The square root of 3121643 is about 1766.8171948450. The cubic root of 3121643 is about 146.1485165398.

Adding to 3121643 its reverse (3461213), we get a palindrome (6582856).

The spelling of 3121643 in words is "three million, one hundred twenty-one thousand, six hundred forty-three".