3138521 has 2 divisors, whose sum is σ = 3138522. Its totient is φ = 3138520.

The previous prime is 3138503. The next prime is 3138529. The reversal of 3138521 is 1258313.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1792921 + 1345600 = 1339^2 + 1160^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3138521 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is equal to p₂₂₆₀₆₇ and since 3138521 and 226067 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (3138529) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1569260 + 1569261.

It is an arithmetic number, because the mean of its divisors is an integer number (1569261).

Almost surely, 2^3138521 is an apocalyptic number.

It is an amenable number.

3138521 is a deficient number, since it is larger than the sum of its proper divisors (1).

3138521 is an equidigital number, since it uses as much as digits as its factorization.

3138521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 720, while the sum is 23.

The square root of 3138521 is about 1771.5871415203. The cubic root of 3138521 is about 146.4114403006.

The spelling of 3138521 in words is "three million, one hundred thirty-eight thousand, five hundred twenty-one".