20782291 has 2 divisors, whose sum is σ = 20782292. Its totient is φ = 20782290.

The previous prime is 20782277. The next prime is 20782303. The reversal of 20782291 is 19228702.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20782291 - 2⁷ = 20782163 is a prime.

It is a zygodrome in base 3.

It is not a weakly prime, because it can be changed into another prime (20782231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10391145 + 10391146.

It is an arithmetic number, because the mean of its divisors is an integer number (10391146).

Almost surely, 2^20782291 is an apocalyptic number.

20782291 is a deficient number, since it is larger than the sum of its proper divisors (1).

20782291 is an equidigital number, since it uses as much as digits as its factorization.

20782291 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 20782291 is about 4558.7598094219. The cubic root of 20782291 is about 274.9357028743.

The spelling of 20782291 in words is "twenty million, seven hundred eighty-two thousand, two hundred ninety-one".