20806842 has 16 divisors (see below), whose sum is σ = 47558592. Its totient is φ = 5944800.

The previous prime is 20806829. The next prime is 20806847. The reversal of 20806842 is 24860802.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (20806847) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 247659 + ... + 247742.

It is an arithmetic number, because the mean of its divisors is an integer number (2972412).

Almost surely, 2^20806842 is an apocalyptic number.

20806842 is an abundant number, since it is smaller than the sum of its proper divisors (26751750).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20806842 is a wasteful number, since it uses less digits than its factorization.

20806842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 495413.

The product of its (nonzero) digits is 6144, while the sum is 30.

The square root of 20806842 is about 4561.4517425925. The cubic root of 20806842 is about 275.0439246642.

The spelling of 20806842 in words is "twenty million, eight hundred six thousand, eight hundred forty-two".