20782579 has 2 divisors, whose sum is σ = 20782580. Its totient is φ = 20782578.

The previous prime is 20782571. The next prime is 20782591. The reversal of 20782579 is 97528702.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20782579 - 2³ = 20782571 is a prime.

It is not a weakly prime, because it can be changed into another prime (20782571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10391289 + 10391290.

It is an arithmetic number, because the mean of its divisors is an integer number (10391290).

Almost surely, 2^20782579 is an apocalyptic number.

20782579 is a deficient number, since it is larger than the sum of its proper divisors (1).

20782579 is an equidigital number, since it uses as much as digits as its factorization.

20782579 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 70560, while the sum is 40.

The square root of 20782579 is about 4558.7913968507. The cubic root of 20782579 is about 274.9369728838.

The spelling of 20782579 in words is "twenty million, seven hundred eighty-two thousand, five hundred seventy-nine".