20225551 has 4 divisors (see below), whose sum is σ = 20289672. Its totient is φ = 20161432.

The previous prime is 20225539. The next prime is 20225561. The reversal of 20225551 is 15552202.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20225551 - 2⁹ = 20225039 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20225521) 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 in 3 ways as a sum of consecutive naturals, for example, 31585 + ... + 32218.

It is an arithmetic number, because the mean of its divisors is an integer number (5072418).

Almost surely, 2^20225551 is an apocalyptic number.

20225551 is a deficient number, since it is larger than the sum of its proper divisors (64121).

20225551 is an equidigital number, since it uses as much as digits as its factorization.

20225551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64120.

The product of its (nonzero) digits is 1000, while the sum is 22.

The square root of 20225551 is about 4497.2826239853. The cubic root of 20225551 is about 272.4583489914.

Adding to 20225551 its reverse (15552202), we get a palindrome (35777753).

The spelling of 20225551 in words is "twenty million, two hundred twenty-five thousand, five hundred fifty-one".