20425857 has 16 divisors (see below), whose sum is σ = 29031552. Its totient is φ = 12729600.

The previous prime is 20425849. The next prime is 20425879. The reversal of 20425857 is 75852402.

It is not a de Polignac number, because 20425857 - 2³ = 20425849 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20425897) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6732 + ... + 9282.

It is an arithmetic number, because the mean of its divisors is an integer number (1814472).

Almost surely, 2^20425857 is an apocalyptic number.

It is an amenable number.

20425857 is a deficient number, since it is larger than the sum of its proper divisors (8605695).

20425857 is a wasteful number, since it uses less digits than its factorization.

20425857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2728.

The product of its (nonzero) digits is 22400, while the sum is 33.

The square root of 20425857 is about 4519.4974278121. The cubic root of 20425857 is about 273.3548365329.

The spelling of 20425857 in words is "twenty million, four hundred twenty-five thousand, eight hundred fifty-seven".