20420818 has 16 divisors (see below), whose sum is σ = 34320384. Its totient is φ = 9030960.

The previous prime is 20420773. The next prime is 20420821. The reversal of 20420818 is 81802402.

It is a junction number, because it is equal to n+sod(n) for n = 20420792 and 20420801.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11730 + ... + 13357.

It is an arithmetic number, because the mean of its divisors is an integer number (2145024).

Almost surely, 2^20420818 is an apocalyptic number.

20420818 is a deficient number, since it is larger than the sum of its proper divisors (13899566).

20420818 is a wasteful number, since it uses less digits than its factorization.

20420818 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25137.

The product of its (nonzero) digits is 1024, while the sum is 25.

The square root of 20420818 is about 4518.9399199370. The cubic root of 20420818 is about 273.3323560676.

The spelling of 20420818 in words is "twenty million, four hundred twenty thousand, eight hundred eighteen".