20782020 has 48 divisors (see below), whose sum is σ = 66503808. Its totient is φ = 4750080.

The previous prime is 20781931. The next prime is 20782031. The reversal of 20782020 is 2028702.

It is a Harshad number since it is a multiple of its sum of digits (21).

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 15 ways as a sum of consecutive naturals, for example, 24321 + ... + 25160.

It is an arithmetic number, because the mean of its divisors is an integer number (1385496).

Almost surely, 2^20782020 is an apocalyptic number.

20782020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20782020 is an abundant number, since it is smaller than the sum of its proper divisors (45721788).

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

20782020 is a wasteful number, since it uses less digits than its factorization.

20782020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49500 (or 49498 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 21.

The square root of 20782020 is about 4558.7300863289. The cubic root of 20782020 is about 274.9345078200.

The spelling of 20782020 in words is "twenty million, seven hundred eighty-two thousand, twenty".