20620820 has 36 divisors (see below), whose sum is σ = 47603892. Its totient is φ = 7497600.

The previous prime is 20620807. The next prime is 20620823. The reversal of 20620820 is 2802602.

It can be written as a sum of positive squares in 2 ways, for example, as 8690704 + 11930116 = 2948^2 + 3454^2 .

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 = 20620792 and 20620801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20620823) 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 11 ways as a sum of consecutive naturals, for example, 1841 + ... + 6680.

Almost surely, 2^20620820 is an apocalyptic number.

20620820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20620820 is an abundant number, since it is smaller than the sum of its proper divisors (26983072).

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

20620820 is a wasteful number, since it uses less digits than its factorization.

20620820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8552 (or 8539 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 20620820 is about 4541.0153049731. The cubic root of 20620820 is about 274.2217999122.

The spelling of 20620820 in words is "twenty million, six hundred twenty thousand, eight hundred twenty".