51803821 has 8 divisors (see below), whose sum is σ = 53561088. Its totient is φ = 50052000.

The previous prime is 51803813. The next prime is 51803837. The reversal of 51803821 is 12830815.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a 3-Lehmer number, since φ(51803821) divides (51803821-1)³.

It is a cyclic number.

It is not a de Polignac number, because 51803821 - 2³ = 51803813 is a prime.

It is a deceptive number, since it divides R_51803820.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51803821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51803881) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29241 + ... + 30961.

It is an arithmetic number, because the mean of its divisors is an integer number (6695136).

It is a Poulet number, since it divides 2^51803820-1.

Almost surely, 2^51803821 is an apocalyptic number.

It is an amenable number.

51803821 is a deficient number, since it is larger than the sum of its proper divisors (1757267).

51803821 is a wasteful number, since it uses less digits than its factorization.

51803821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2723.

The product of its (nonzero) digits is 1920, while the sum is 28.

The square root of 51803821 is about 7197.4871309367. The cubic root of 51803821 is about 372.7811393513.

The spelling of 51803821 in words is "fifty-one million, eight hundred three thousand, eight hundred twenty-one".