20403220 has 24 divisors (see below), whose sum is σ = 42999264. Its totient is φ = 8132256.

The previous prime is 20403197. The next prime is 20403221. The reversal of 20403220 is 2230402.

It is a self number, because there is not a number n which added to its sum of digits gives 20403220.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20403221) 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 7 ways as a sum of consecutive naturals, for example, 4479 + ... + 7801.

It is an arithmetic number, because the mean of its divisors is an integer number (1791636).

Almost surely, 2^20403220 is an apocalyptic number.

20403220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20403220 is an abundant number, since it is smaller than the sum of its proper divisors (22596044).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20403220 is a wasteful number, since it uses less digits than its factorization.

20403220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3639 (or 3637 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 13.

The square root of 20403220 is about 4516.9923621808. The cubic root of 20403220 is about 273.2538171767.

Adding to 20403220 its reverse (2230402), we get a palindrome (22633622).

The spelling of 20403220 in words is "twenty million, four hundred three thousand, two hundred twenty".