3111921 has 6 divisors (see below), whose sum is σ = 4495010. Its totient is φ = 2074608.

The previous prime is 3111863. The next prime is 3111931. The reversal of 3111921 is 1291113.

It can be written as a sum of positive squares in only one way, i.e., 3111696 + 225 = 1764^2 + 15^2 .

It is not a de Polignac number, because 3111921 - 2¹³ = 3103729 is a prime.

It is a Duffinian number.

3111921 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 3111894 and 3111903.

It is not an unprimeable number, because it can be changed into a prime (3111931) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 172876 + ... + 172893.

Almost surely, 2^3111921 is an apocalyptic number.

It is an amenable number.

3111921 is a deficient number, since it is larger than the sum of its proper divisors (1383089).

3111921 is a wasteful number, since it uses less digits than its factorization.

3111921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 345775 (or 345772 counting only the distinct ones).

The product of its digits is 54, while the sum is 18.

The square root of 3111921 is about 1764.0637743574. The cubic root of 3111921 is about 145.9966378159.

The spelling of 3111921 in words is "three million, one hundred eleven thousand, nine hundred twenty-one".