20726539 has 2 divisors, whose sum is σ = 20726540. Its totient is φ = 20726538.

The previous prime is 20726521. The next prime is 20726543. The reversal of 20726539 is 93562702.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20726539 - 2¹¹ = 20724491 is a prime.

It is not a weakly prime, because it can be changed into another prime (20726509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10363269 + 10363270.

It is an arithmetic number, because the mean of its divisors is an integer number (10363270).

Almost surely, 2^20726539 is an apocalyptic number.

20726539 is a deficient number, since it is larger than the sum of its proper divisors (1).

20726539 is an equidigital number, since it uses as much as digits as its factorization.

20726539 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 22680, while the sum is 34.

The square root of 20726539 is about 4552.6408819497. The cubic root of 20726539 is about 274.6896289034.

The spelling of 20726539 in words is "twenty million, seven hundred twenty-six thousand, five hundred thirty-nine".