21628195 has 4 divisors (see below), whose sum is σ = 25953840. Its totient is φ = 17302552.

The previous prime is 21628193. The next prime is 21628219. The reversal of 21628195 is 59182612.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21628195 - 2¹ = 21628193 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21628195.

It is not an unprimeable number, because it can be changed into a prime (21628193) 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, 2162815 + ... + 2162824.

It is an arithmetic number, because the mean of its divisors is an integer number (6488460).

Almost surely, 2^21628195 is an apocalyptic number.

21628195 is a deficient number, since it is larger than the sum of its proper divisors (4325645).

21628195 is an equidigital number, since it uses as much as digits as its factorization.

21628195 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4325644.

The product of its digits is 8640, while the sum is 34.

The square root of 21628195 is about 4650.6123252750. The cubic root of 21628195 is about 278.6164528834.

The spelling of 21628195 in words is "twenty-one million, six hundred twenty-eight thousand, one hundred ninety-five".