20228917 has 4 divisors (see below), whose sum is σ = 20571840. Its totient is φ = 19885996.

The previous prime is 20228903. The next prime is 20228927. The reversal of 20228917 is 71982202.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 71982202 = 2 ⋅35991101.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20228917 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 (20228927) 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, 171373 + ... + 171490.

It is an arithmetic number, because the mean of its divisors is an integer number (5142960).

Almost surely, 2^20228917 is an apocalyptic number.

It is an amenable number.

20228917 is a deficient number, since it is larger than the sum of its proper divisors (342923).

20228917 is an equidigital number, since it uses as much as digits as its factorization.

20228917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 342922.

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 20228917 is about 4497.6568343972. The cubic root of 20228917 is about 272.4734626123.

The spelling of 20228917 in words is "twenty million, two hundred twenty-eight thousand, nine hundred seventeen".