5157821 has 2 divisors, whose sum is σ = 5157822. Its totient is φ = 5157820.

The previous prime is 5157793. The next prime is 5157829. The reversal of 5157821 is 1287515.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4687225 + 470596 = 2165^2 + 686^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-5157821 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (5157829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2578910 + 2578911.

It is an arithmetic number, because the mean of its divisors is an integer number (2578911).

Almost surely, 2^5157821 is an apocalyptic number.

It is an amenable number.

5157821 is a deficient number, since it is larger than the sum of its proper divisors (1).

5157821 is an equidigital number, since it uses as much as digits as its factorization.

5157821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2800, while the sum is 29.

The square root of 5157821 is about 2271.0836620433. The cubic root of 5157821 is about 172.7781244634.

The spelling of 5157821 in words is "five million, one hundred fifty-seven thousand, eight hundred twenty-one".