51820805 has 8 divisors (see below), whose sum is σ = 63631392. Its totient is φ = 40492368.

The previous prime is 51820793. The next prime is 51820819. The reversal of 51820805 is 50802815.

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

It is a cyclic number.

It is not a de Polignac number, because 51820805 - 2⁴ = 51820789 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 120299 + ... + 120728.

It is an arithmetic number, because the mean of its divisors is an integer number (7953924).

Almost surely, 2^51820805 is an apocalyptic number.

It is an amenable number.

51820805 is a deficient number, since it is larger than the sum of its proper divisors (11810587).

51820805 is a wasteful number, since it uses less digits than its factorization.

51820805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 241075.

The product of its (nonzero) digits is 3200, while the sum is 29.

The square root of 51820805 is about 7198.6668904735. Note that the first 3 decimals coincide. The cubic root of 51820805 is about 372.8218739468.

It can be divided in two parts, 51820 and 805, that added together give a palindrome (52625).

The spelling of 51820805 in words is "fifty-one million, eight hundred twenty thousand, eight hundred five".