21628834 has 8 divisors (see below), whose sum is σ = 32474268. Its totient is φ = 10804080.

The previous prime is 21628829. The next prime is 21628837. The reversal of 21628834 is 43882612.

It can be written as a sum of positive squares in 2 ways, for example, as 21594609 + 34225 = 4647^2 + 185^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21628834.

It is not an unprimeable number, because it can be changed into a prime (21628837) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2217 + ... + 6940.

Almost surely, 2^21628834 is an apocalyptic number.

21628834 is a deficient number, since it is larger than the sum of its proper divisors (10845434).

21628834 is a wasteful number, since it uses less digits than its factorization.

21628834 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10340.

The product of its digits is 18432, while the sum is 34.

The square root of 21628834 is about 4650.6810253983. The cubic root of 21628834 is about 278.6191967426.

The spelling of 21628834 in words is "twenty-one million, six hundred twenty-eight thousand, eight hundred thirty-four".