20928417 has 4 divisors (see below), whose sum is σ = 27904560. Its totient is φ = 13952276.

The previous prime is 20928407. The next prime is 20928419. The reversal of 20928417 is 71482902.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 20928417 - 2⁶ = 20928353 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20928419) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3488067 + ... + 3488072.

It is an arithmetic number, because the mean of its divisors is an integer number (6976140).

Almost surely, 2^20928417 is an apocalyptic number.

It is an amenable number.

20928417 is a deficient number, since it is larger than the sum of its proper divisors (6976143).

20928417 is an equidigital number, since it uses as much as digits as its factorization.

20928417 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6976142.

The product of its (nonzero) digits is 8064, while the sum is 33.

The square root of 20928417 is about 4574.7586821602. The cubic root of 20928417 is about 275.5785812996.

The spelling of 20928417 in words is "twenty million, nine hundred twenty-eight thousand, four hundred seventeen".