20778224 has 20 divisors (see below), whose sum is σ = 40328520. Its totient is φ = 10370880.

The previous prime is 20778211. The next prime is 20778253. The reversal of 20778224 is 42287702.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17159 + ... + 18329.

It is an arithmetic number, because the mean of its divisors is an integer number (2016426).

Almost surely, 2^20778224 is an apocalyptic number.

It is an amenable number.

20778224 is a deficient number, since it is larger than the sum of its proper divisors (19550296).

20778224 is a wasteful number, since it uses less digits than its factorization.

20778224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2288 (or 2282 counting only the distinct ones).

The product of its (nonzero) digits is 12544, while the sum is 32.

The square root of 20778224 is about 4558.3137232972. The cubic root of 20778224 is about 274.9177671480.

It can be divided in two parts, 2077 and 8224, that added together give a palindrome (10301).

The spelling of 20778224 in words is "twenty million, seven hundred seventy-eight thousand, two hundred twenty-four".