20428807 has 16 divisors (see below), whose sum is σ = 24514560. Its totient is φ = 16644672.

The previous prime is 20428801. The next prime is 20428817. The reversal of 20428807 is 70882402.

It is a cyclic number.

It is not a de Polignac number, because 20428807 - 2³ = 20428799 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20428801) 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 15 ways as a sum of consecutive naturals, for example, 35619 + ... + 36187.

It is an arithmetic number, because the mean of its divisors is an integer number (1532160).

Almost surely, 2^20428807 is an apocalyptic number.

20428807 is a deficient number, since it is larger than the sum of its proper divisors (4085753).

20428807 is a wasteful number, since it uses less digits than its factorization.

20428807 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 822.

The product of its (nonzero) digits is 7168, while the sum is 31.

The square root of 20428807 is about 4519.8237797507. The cubic root of 20428807 is about 273.3679956372.

The spelling of 20428807 in words is "twenty million, four hundred twenty-eight thousand, eight hundred seven".