20525231 has 2 divisors, whose sum is σ = 20525232. Its totient is φ = 20525230.

The previous prime is 20525213. The next prime is 20525251. The reversal of 20525231 is 13252502.

Together with previous prime (20525213) it forms an Ormiston pair, because they use the same digits, order apart.

It is an a-pointer prime, because the next prime (20525251) can be obtained adding 20525231 to its sum of digits (20).

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20525231 is a prime.

It is a super-2 number, since 2×20525231² = 842570215206722, which contains 22 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20525251) 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, 10262615 + 10262616.

It is an arithmetic number, because the mean of its divisors is an integer number (10262616).

Almost surely, 2^20525231 is an apocalyptic number.

20525231 is a deficient number, since it is larger than the sum of its proper divisors (1).

20525231 is an equidigital number, since it uses as much as digits as its factorization.

20525231 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 600, while the sum is 20.

The square root of 20525231 is about 4530.4780101000. The cubic root of 20525231 is about 273.7974198345.

Adding to 20525231 its reverse (13252502), we get a palindrome (33777733).

The spelling of 20525231 in words is "twenty million, five hundred twenty-five thousand, two hundred thirty-one".