20226391 has 2 divisors, whose sum is σ = 20226392. Its totient is φ = 20226390.

The previous prime is 20226389. The next prime is 20226397. The reversal of 20226391 is 19362202.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20226391 - 2¹ = 20226389 is a prime.

Together with 20226389, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20226397) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10113195 + 10113196.

It is an arithmetic number, because the mean of its divisors is an integer number (10113196).

Almost surely, 2^20226391 is an apocalyptic number.

20226391 is a deficient number, since it is larger than the sum of its proper divisors (1).

20226391 is an equidigital number, since it uses as much as digits as its factorization.

20226391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 20226391 is about 4497.3760127434. The cubic root of 20226391 is about 272.4621208185.

Adding to 20226391 its reverse (19362202), we get a palindrome (39588593).

The spelling of 20226391 in words is "twenty million, two hundred twenty-six thousand, three hundred ninety-one".