20451271 has 2 divisors, whose sum is σ = 20451272. Its totient is φ = 20451270.

The previous prime is 20451259. The next prime is 20451311. The reversal of 20451271 is 17215402.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20451271 - 2¹⁹ = 19926983 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20451241) 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, 10225635 + 10225636.

It is an arithmetic number, because the mean of its divisors is an integer number (10225636).

Almost surely, 2^20451271 is an apocalyptic number.

20451271 is a deficient number, since it is larger than the sum of its proper divisors (1).

20451271 is an equidigital number, since it uses as much as digits as its factorization.

20451271 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 560, while the sum is 22.

The square root of 20451271 is about 4522.3081496068. The cubic root of 20451271 is about 273.4681595727.

Adding to 20451271 its reverse (17215402), we get a palindrome (37666673).

The spelling of 20451271 in words is "twenty million, four hundred fifty-one thousand, two hundred seventy-one".