21830428 has 6 divisors (see below), whose sum is σ = 38203256. Its totient is φ = 10915212.

The previous prime is 21830387. The next prime is 21830453. The reversal of 21830428 is 82403812.

It is a junction number, because it is equal to n+sod(n) for n = 21830396 and 21830405.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2728800 + ... + 2728807.

Almost surely, 2^21830428 is an apocalyptic number.

It is an amenable number.

21830428 is a deficient number, since it is larger than the sum of its proper divisors (16372828).

21830428 is a wasteful number, since it uses less digits than its factorization.

21830428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5457611 (or 5457609 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 28.

The square root of 21830428 is about 4672.3043565247. The cubic root of 21830428 is about 279.4821551091.

The spelling of 21830428 in words is "twenty-one million, eight hundred thirty thousand, four hundred twenty-eight".