20210928 has 40 divisors (see below), whose sum is σ = 54484608. Its totient is φ = 6443712.

The previous prime is 20210923. The next prime is 20210929. The reversal of 20210928 is 82901202.

It is a super-2 number, since 2×20210928² = 816963221242368, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a junction number, because it is equal to n+sod(n) for n = 20210898 and 20210907.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20210923) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 8050 + ... + 10257.

Almost surely, 2^20210928 is an apocalyptic number.

It is an amenable number.

20210928 is an abundant number, since it is smaller than the sum of its proper divisors (34273680).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20210928 is a wasteful number, since it uses less digits than its factorization.

20210928 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18341 (or 18335 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 24.

The square root of 20210928 is about 4495.6565705134. The cubic root of 20210928 is about 272.3926710279.

The spelling of 20210928 in words is "twenty million, two hundred ten thousand, nine hundred twenty-eight".