20255813 has 2 divisors, whose sum is σ = 20255814. Its totient is φ = 20255812.

The previous prime is 20255783. The next prime is 20255839. The reversal of 20255813 is 31855202.

It is an a-pointer prime, because the next prime (20255839) can be obtained adding 20255813 to its sum of digits (26).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14577124 + 5678689 = 3818^2 + 2383^2 .

It is a cyclic number.

It is not a de Polignac number, because 20255813 - 2¹⁶ = 20190277 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20255413) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10127906 + 10127907.

It is an arithmetic number, because the mean of its divisors is an integer number (10127907).

Almost surely, 2^20255813 is an apocalyptic number.

It is an amenable number.

20255813 is a deficient number, since it is larger than the sum of its proper divisors (1).

20255813 is an equidigital number, since it uses as much as digits as its factorization.

20255813 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2400, while the sum is 26.

The square root of 20255813 is about 4500.6458425430. The cubic root of 20255813 is about 272.5941677185.

The spelling of 20255813 in words is "twenty million, two hundred fifty-five thousand, eight hundred thirteen".