3821813 has 2 divisors, whose sum is σ = 3821814. Its totient is φ = 3821812.

The previous prime is 3821809. The next prime is 3821819. The reversal of 3821813 is 3181283.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2289169 + 1532644 = 1513^2 + 1238^2 .

It is a cyclic number.

It is not a de Polignac number, because 3821813 - 2² = 3821809 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3821819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1910906 + 1910907.

It is an arithmetic number, because the mean of its divisors is an integer number (1910907).

Almost surely, 2^3821813 is an apocalyptic number.

It is an amenable number.

3821813 is a deficient number, since it is larger than the sum of its proper divisors (1).

3821813 is an equidigital number, since it uses as much as digits as its factorization.

3821813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1152, while the sum is 26.

The square root of 3821813 is about 1954.9457792993. The cubic root of 3821813 is about 156.3470931475.

The spelling of 3821813 in words is "three million, eight hundred twenty-one thousand, eight hundred thirteen".