20916020 has 12 divisors (see below), whose sum is σ = 43923684. Its totient is φ = 8366400.

The previous prime is 20916019. The next prime is 20916029. The reversal of 20916020 is 2061902.

It can be written as a sum of positive squares in 2 ways, for example, as 4963984 + 15952036 = 2228^2 + 3994^2 .

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 1045801 = 20916020 / (2 + 0 + 9 + 1 + 6 + 0 + 2 + 0).

It is a junction number, because it is equal to n+sod(n) for n = 20915983 and 20916001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20916029) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 522881 + ... + 522920.

It is an arithmetic number, because the mean of its divisors is an integer number (3660307).

Almost surely, 2^20916020 is an apocalyptic number.

20916020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20916020 is an abundant number, since it is smaller than the sum of its proper divisors (23007664).

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

20916020 is a wasteful number, since it uses less digits than its factorization.

20916020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1045810 (or 1045808 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 20916020 is about 4573.4035465942. The cubic root of 20916020 is about 275.5241573322.

Adding to 20916020 its reverse (2061902), we get a palindrome (22977922).

The spelling of 20916020 in words is "twenty million, nine hundred sixteen thousand, twenty".