20507849 has 2 divisors, whose sum is σ = 20507850. Its totient is φ = 20507848.

The previous prime is 20507807. The next prime is 20507857. The reversal of 20507849 is 94870502.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17808400 + 2699449 = 4220^2 + 1643^2 .

It is a cyclic number.

It is not a de Polignac number, because 20507849 - 2¹² = 20503753 is a prime.

It is not a weakly prime, because it can be changed into another prime (20507549) 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, 10253924 + 10253925.

It is an arithmetic number, because the mean of its divisors is an integer number (10253925).

Almost surely, 2^20507849 is an apocalyptic number.

It is an amenable number.

20507849 is a deficient number, since it is larger than the sum of its proper divisors (1).

20507849 is an equidigital number, since it uses as much as digits as its factorization.

20507849 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20160, while the sum is 35.

The square root of 20507849 is about 4528.5592631653. The cubic root of 20507849 is about 273.7201086327.

The spelling of 20507849 in words is "twenty million, five hundred seven thousand, eight hundred forty-nine".