3612821 has 2 divisors, whose sum is σ = 3612822. Its totient is φ = 3612820.

The previous prime is 3612811. The next prime is 3612853. The reversal of 3612821 is 1282163.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2640625 + 972196 = 1625^2 + 986^2 .

It is an emirp because it is prime and its reverse (1282163) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3612821 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3612811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1806410 + 1806411.

It is an arithmetic number, because the mean of its divisors is an integer number (1806411).

Almost surely, 2^3612821 is an apocalyptic number.

It is an amenable number.

3612821 is a deficient number, since it is larger than the sum of its proper divisors (1).

3612821 is an equidigital number, since it uses as much as digits as its factorization.

3612821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 576, while the sum is 23.

The square root of 3612821 is about 1900.7422234485. The cubic root of 3612821 is about 153.4436126432.

Adding to 3612821 its reverse (1282163), we get a palindrome (4894984).

The spelling of 3612821 in words is "three million, six hundred twelve thousand, eight hundred twenty-one".