20123428 has 12 divisors (see below), whose sum is σ = 37925020. Its totient is φ = 9287712.

The previous prime is 20123417. The next prime is 20123431. The reversal of 20123428 is 82432102.

It can be written as a sum of positive squares in 2 ways, for example, as 5053504 + 15069924 = 2248^2 + 3882^2 .

It is a junction number, because it is equal to n+sod(n) for n = 20123399 and 20123408.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 193443 + ... + 193546.

Almost surely, 2^20123428 is an apocalyptic number.

It is an amenable number.

20123428 is a deficient number, since it is larger than the sum of its proper divisors (17801592).

20123428 is a wasteful number, since it uses less digits than its factorization.

20123428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 387006 (or 387004 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 22.

The square root of 20123428 is about 4485.9143995400. The cubic root of 20123428 is about 271.9990087911. Note that the first 3 decimals are identical.

Adding to 20123428 its product of nonzero digits (768), we get a square (20124196 = 4486²).

The spelling of 20123428 in words is "twenty million, one hundred twenty-three thousand, four hundred twenty-eight".