20928145 has 16 divisors (see below), whose sum is σ = 29289600. Its totient is φ = 14349552.

The previous prime is 20928107. The next prime is 20928157. The reversal of 20928145 is 54182902.

It is not a de Polignac number, because 20928145 - 2¹³ = 20919953 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4387 + ... + 7816.

It is an arithmetic number, because the mean of its divisors is an integer number (1830600).

Almost surely, 2^20928145 is an apocalyptic number.

It is an amenable number.

20928145 is a deficient number, since it is larger than the sum of its proper divisors (8361455).

20928145 is an equidigital number, since it uses as much as digits as its factorization.

20928145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12229 (or 12215 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 31.

The square root of 20928145 is about 4574.7289537196. The cubic root of 20928145 is about 275.5773874253.

The spelling of 20928145 in words is "twenty million, nine hundred twenty-eight thousand, one hundred forty-five".