20262581 has 2 divisors, whose sum is σ = 20262582. Its totient is φ = 20262580.

The previous prime is 20262533. The next prime is 20262587. The reversal of 20262581 is 18526202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17355556 + 2907025 = 4166^2 + 1705^2 .

It is a cyclic number.

It is not a de Polignac number, because 20262581 - 2¹⁴ = 20246197 is a prime.

It is a super-2 number, since 2×20262581² = 821144377563122, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20262581.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20262587) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10131290 + 10131291.

It is an arithmetic number, because the mean of its divisors is an integer number (10131291).

Almost surely, 2^20262581 is an apocalyptic number.

It is an amenable number.

20262581 is a deficient number, since it is larger than the sum of its proper divisors (1).

20262581 is an equidigital number, since it uses as much as digits as its factorization.

20262581 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1920, while the sum is 26.

The square root of 20262581 is about 4501.3976718348. The cubic root of 20262581 is about 272.6245246319.

Adding to 20262581 its reverse (18526202), we get a palindrome (38788783).

The spelling of 20262581 in words is "twenty million, two hundred sixty-two thousand, five hundred eighty-one".