20321818 has 8 divisors (see below), whose sum is σ = 33253920. Its totient is φ = 9237180.

The previous prime is 20321759. The next prime is 20321867. The reversal of 20321818 is 81812302.

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

It is a junction number, because it is equal to n+sod(n) for n = 20321792 and 20321801.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 461838 + ... + 461881.

It is an arithmetic number, because the mean of its divisors is an integer number (4156740).

Almost surely, 2^20321818 is an apocalyptic number.

20321818 is a deficient number, since it is larger than the sum of its proper divisors (12932102).

20321818 is a wasteful number, since it uses less digits than its factorization.

20321818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 923732.

The product of its (nonzero) digits is 768, while the sum is 25.

The square root of 20321818 is about 4507.9727150905. The cubic root of 20321818 is about 272.8899358186.

The spelling of 20321818 in words is "twenty million, three hundred twenty-one thousand, eight hundred eighteen".