20001028 has 6 divisors (see below), whose sum is σ = 35001806. Its totient is φ = 10000512.

The previous prime is 20001019. The next prime is 20001029. The reversal of 20001028 is 82010002.

It can be written as a sum of positive squares in only one way, i.e., 14992384 + 5008644 = 3872^2 + 2238^2 .

It is a super-2 number, since 2×20001028² = 800082242113568, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20000999 and 20001017.

It is not an unprimeable number, because it can be changed into a prime (20001029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2500125 + ... + 2500132.

Almost surely, 2^20001028 is an apocalyptic number.

It is an amenable number.

20001028 is a deficient number, since it is larger than the sum of its proper divisors (15000778).

20001028 is a wasteful number, since it uses less digits than its factorization.

20001028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5000261 (or 5000259 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

The square root of 20001028 is about 4472.2508874168. The cubic root of 20001028 is about 271.4464122820.

The spelling of 20001028 in words is "twenty million, one thousand, twenty-eight".