5251821 has 4 divisors (see below), whose sum is σ = 7002432. Its totient is φ = 3501212.

The previous prime is 5251819. The next prime is 5251859. The reversal of 5251821 is 1281525.

5251821 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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.

It is a cyclic number.

It is not a de Polignac number, because 5251821 - 2¹ = 5251819 is a prime.

It is a D-number.

It is a junction number, because it is equal to n+sod(n) for n = 5251791 and 5251800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5256821) 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, 875301 + ... + 875306.

It is an arithmetic number, because the mean of its divisors is an integer number (1750608).

Almost surely, 2^5251821 is an apocalyptic number.

It is an amenable number.

5251821 is a deficient number, since it is larger than the sum of its proper divisors (1750611).

5251821 is a wasteful number, since it uses less digits than its factorization.

5251821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1750610.

The product of its digits is 800, while the sum is 24.

The square root of 5251821 is about 2291.6851878039. The cubic root of 5251821 is about 173.8214246659.

It can be divided in two parts, 525 and 1821, that added together give a triangular number (2346 = T₆₈).

The spelling of 5251821 in words is "five million, two hundred fifty-one thousand, eight hundred twenty-one".