5637821 has 4 divisors (see below), whose sum is σ = 6443232. Its totient is φ = 4832412.

The previous prime is 5637817. The next prime is 5637823. The reversal of 5637821 is 1287365.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1287365 = 5 ⋅257473.

It is a cyclic number.

It is not a de Polignac number, because 5637821 - 2² = 5637817 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5637823) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 402695 + ... + 402708.

It is an arithmetic number, because the mean of its divisors is an integer number (1610808).

Almost surely, 2^5637821 is an apocalyptic number.

It is an amenable number.

5637821 is a deficient number, since it is larger than the sum of its proper divisors (805411).

5637821 is an equidigital number, since it uses as much as digits as its factorization.

5637821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 805410.

The product of its digits is 10080, while the sum is 32.

The square root of 5637821 is about 2374.4096108296. The cubic root of 5637821 is about 177.9796824851.

The spelling of 5637821 in words is "five million, six hundred thirty-seven thousand, eight hundred twenty-one".