20782417 has 2 divisors, whose sum is σ = 20782418. Its totient is φ = 20782416.

The previous prime is 20782393. The next prime is 20782469. The reversal of 20782417 is 71428702.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20757136 + 25281 = 4556^2 + 159^2 .

It is a cyclic number.

It is not a de Polignac number, because 20782417 - 2¹¹ = 20780369 is a prime.

It is not a weakly prime, because it can be changed into another prime (20782477) by changing a digit.

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 as a sum of consecutive naturals, namely, 10391208 + 10391209.

It is an arithmetic number, because the mean of its divisors is an integer number (10391209).

Almost surely, 2^20782417 is an apocalyptic number.

It is an amenable number.

20782417 is a deficient number, since it is larger than the sum of its proper divisors (1).

20782417 is an equidigital number, since it uses as much as digits as its factorization.

20782417 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6272, while the sum is 31.

The square root of 20782417 is about 4558.7736289489. The cubic root of 20782417 is about 274.9362585049.

The spelling of 20782417 in words is "twenty million, seven hundred eighty-two thousand, four hundred seventeen".