3091021 has 2 divisors, whose sum is σ = 3091022. Its totient is φ = 3091020.

The previous prime is 3091019. The next prime is 3091027. The reversal of 3091021 is 1201903.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2368521 + 722500 = 1539^2 + 850^2 .

It is a cyclic number.

It is not a de Polignac number, because 3091021 - 2¹ = 3091019 is a prime.

Together with 3091019, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 3090986 and 3091004.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3091027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1545510 + 1545511.

It is an arithmetic number, because the mean of its divisors is an integer number (1545511).

Almost surely, 2^3091021 is an apocalyptic number.

It is an amenable number.

3091021 is a deficient number, since it is larger than the sum of its proper divisors (1).

3091021 is an equidigital number, since it uses as much as digits as its factorization.

3091021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 54, while the sum is 16.

The square root of 3091021 is about 1758.1299724423. The cubic root of 3091021 is about 145.6690602677.

Adding to 3091021 its reverse (1201903), we get a palindrome (4292924).

The spelling of 3091021 in words is "three million, ninety-one thousand, twenty-one".