20351228 has 12 divisors (see below), whose sum is σ = 37163280. Its totient is φ = 9733152.

The previous prime is 20351207. The next prime is 20351239. The reversal of 20351228 is 82215302.

It is a super-2 number, since 2×20351228² = 828344962215968, which contains 22 as substring.

It is a hoax number, since the sum of its digits (23) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 110513 + ... + 110696.

It is an arithmetic number, because the mean of its divisors is an integer number (3096940).

Almost surely, 2^20351228 is an apocalyptic number.

It is an amenable number.

20351228 is a deficient number, since it is larger than the sum of its proper divisors (16812052).

20351228 is a wasteful number, since it uses less digits than its factorization.

20351228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221236 (or 221234 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 23.

The square root of 20351228 is about 4511.2335341900. The cubic root of 20351228 is about 273.0215156555.

The spelling of 20351228 in words is "twenty million, three hundred fifty-one thousand, two hundred twenty-eight".