5109821 has 2 divisors, whose sum is σ = 5109822. Its totient is φ = 5109820.

The previous prime is 5109791. The next prime is 5109847. The reversal of 5109821 is 1289015.

It is a happy number.

It is an a-pointer prime, because the next prime (5109847) can be obtained adding 5109821 to its sum of digits (26).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4452100 + 657721 = 2110^2 + 811^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-5109821 is a prime.

It is a super-2 number, since 2×5109821² = 52220541304082, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (5109121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2554910 + 2554911.

It is an arithmetic number, because the mean of its divisors is an integer number (2554911).

Almost surely, 2^5109821 is an apocalyptic number.

It is an amenable number.

5109821 is a deficient number, since it is larger than the sum of its proper divisors (1).

5109821 is an equidigital number, since it uses as much as digits as its factorization.

5109821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 720, while the sum is 26.

The square root of 5109821 is about 2260.4913182757. The cubic root of 5109821 is about 172.2404807250.

The spelling of 5109821 in words is "five million, one hundred nine thousand, eight hundred twenty-one".