20169428 has 6 divisors (see below), whose sum is σ = 35296506. Its totient is φ = 10084712.

The previous prime is 20169427. The next prime is 20169481. The reversal of 20169428 is 82496102.

It can be written as a sum of positive squares in only one way, i.e., 15382084 + 4787344 = 3922^2 + 2188^2 .

It is a junction number, because it is equal to n+sod(n) for n = 20169394 and 20169403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20169421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2521175 + ... + 2521182.

It is an arithmetic number, because the mean of its divisors is an integer number (5882751).

Almost surely, 2^20169428 is an apocalyptic number.

It is an amenable number.

20169428 is a deficient number, since it is larger than the sum of its proper divisors (15127078).

20169428 is a wasteful number, since it uses less digits than its factorization.

20169428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5042361 (or 5042359 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 32.

The square root of 20169428 is about 4491.0386326550. The cubic root of 20169428 is about 272.2061046005.

The spelling of 20169428 in words is "twenty million, one hundred sixty-nine thousand, four hundred twenty-eight".