20406620 has 24 divisors (see below), whose sum is σ = 46150944. Its totient is φ = 7534656.

The previous prime is 20406611. The next prime is 20406641. The reversal of 20406620 is 2660402.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 20406592 and 20406601.

It is a congruent number.

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, 38984 + ... + 39503.

It is an arithmetic number, because the mean of its divisors is an integer number (1922956).

Almost surely, 2^20406620 is an apocalyptic number.

20406620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20406620 is an abundant number, since it is smaller than the sum of its proper divisors (25744324).

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

20406620 is a wasteful number, since it uses less digits than its factorization.

20406620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78509 (or 78507 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

The square root of 20406620 is about 4517.3687031280. The cubic root of 20406620 is about 273.2689947055.

The spelling of 20406620 in words is "twenty million, four hundred six thousand, six hundred twenty".