5139821 has 2 divisors, whose sum is σ = 5139822. Its totient is φ = 5139820.

The previous prime is 5139811. The next prime is 5139859. The reversal of 5139821 is 1289315.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4791721 + 348100 = 2189^2 + 590^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-5139821 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (5139811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2569910 + 2569911.

It is an arithmetic number, because the mean of its divisors is an integer number (2569911).

Almost surely, 2^5139821 is an apocalyptic number.

It is an amenable number.

5139821 is a deficient number, since it is larger than the sum of its proper divisors (1).

5139821 is an equidigital number, since it uses as much as digits as its factorization.

5139821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2160, while the sum is 29.

The square root of 5139821 is about 2267.1173326495. The cubic root of 5139821 is about 172.5769005303.

The spelling of 5139821 in words is "five million, one hundred thirty-nine thousand, eight hundred twenty-one".