20225591 has 2 divisors, whose sum is σ = 20225592. Its totient is φ = 20225590.

The previous prime is 20225573. The next prime is 20225593. The reversal of 20225591 is 19552202.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20225591 - 2¹⁴ = 20209207 is a prime.

Together with 20225593, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20225591.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20225593) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10112795 + 10112796.

It is an arithmetic number, because the mean of its divisors is an integer number (10112796).

Almost surely, 2^20225591 is an apocalyptic number.

20225591 is a deficient number, since it is larger than the sum of its proper divisors (1).

20225591 is an equidigital number, since it uses as much as digits as its factorization.

20225591 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1800, while the sum is 26.

The square root of 20225591 is about 4497.2870711130. The cubic root of 20225591 is about 272.4585286045.

Adding to 20225591 its reverse (19552202), we get a palindrome (39777793).

The spelling of 20225591 in words is "twenty million, two hundred twenty-five thousand, five hundred ninety-one".