51802209 has 24 divisors (see below), whose sum is σ = 78204672. Its totient is φ = 33003360.

The previous prime is 51802181. The next prime is 51802241. The reversal of 51802209 is 90220815.

It is not a de Polignac number, because 51802209 - 2⁹ = 51801697 is a prime.

It is not an unprimeable number, because it can be changed into a prime (51802249) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 22039 + ... + 24275.

It is an arithmetic number, because the mean of its divisors is an integer number (3258528).

Almost surely, 2^51802209 is an apocalyptic number.

It is an amenable number.

51802209 is a deficient number, since it is larger than the sum of its proper divisors (26402463).

51802209 is a wasteful number, since it uses less digits than its factorization.

51802209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2357 (or 2354 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 51802209 is about 7197.3751465378. The cubic root of 51802209 is about 372.7772726517. Note that the first 3 decimals are identical.

The spelling of 51802209 in words is "fifty-one million, eight hundred two thousand, two hundred nine".