20725171 has 2 divisors, whose sum is σ = 20725172. Its totient is φ = 20725170.

The previous prime is 20725153. The next prime is 20725241. The reversal of 20725171 is 17152702.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20725171 - 2⁹ = 20724659 is a prime.

It is not a weakly prime, because it can be changed into another prime (20722171) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10362585 + 10362586.

It is an arithmetic number, because the mean of its divisors is an integer number (10362586).

Almost surely, 2^20725171 is an apocalyptic number.

20725171 is a deficient number, since it is larger than the sum of its proper divisors (1).

20725171 is an equidigital number, since it uses as much as digits as its factorization.

20725171 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 980, while the sum is 25.

The square root of 20725171 is about 4552.4906370030. The cubic root of 20725171 is about 274.6835853847.

Adding to 20725171 its reverse (17152702), we get a palindrome (37877873).

The spelling of 20725171 in words is "twenty million, seven hundred twenty-five thousand, one hundred seventy-one".