21063428 has 12 divisors (see below), whose sum is σ = 37380672. Its totient is φ = 10383240.

The previous prime is 21063403. The next prime is 21063451. The reversal of 21063428 is 82436012.

It is a super-2 number, since 2×21063428² = 887335998222368, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21063397 and 21063406.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36800 + ... + 37367.

It is an arithmetic number, because the mean of its divisors is an integer number (3115056).

Almost surely, 2^21063428 is an apocalyptic number.

It is an amenable number.

21063428 is a deficient number, since it is larger than the sum of its proper divisors (16317244).

21063428 is a wasteful number, since it uses less digits than its factorization.

21063428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74242 (or 74240 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 26.

The square root of 21063428 is about 4589.4910393202. The cubic root of 21063428 is about 276.1699051870.

The spelling of 21063428 in words is "twenty-one million, sixty-three thousand, four hundred twenty-eight".