20928475 has 6 divisors (see below), whose sum is σ = 25951340. Its totient is φ = 16742760.

The previous prime is 20928473. The next prime is 20928499. The reversal of 20928475 is 57482902.

It is not a de Polignac number, because 20928475 - 2¹ = 20928473 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20928473) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 418545 + ... + 418594.

Almost surely, 2^20928475 is an apocalyptic number.

20928475 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

20928475 is a deficient number, since it is larger than the sum of its proper divisors (5022865).

20928475 is an equidigital number, since it uses as much as digits as its factorization.

20928475 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 837149 (or 837144 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 37.

The square root of 20928475 is about 4574.7650212880. The cubic root of 20928475 is about 275.5788358744.

The spelling of 20928475 in words is "twenty million, nine hundred twenty-eight thousand, four hundred seventy-five".