21919255 has 8 divisors (see below), whose sum is σ = 27687600. Its totient is φ = 16612416.

The previous prime is 21919237. The next prime is 21919259. The reversal of 21919255 is 55291912.

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

It is a cyclic number.

It is not a de Polignac number, because 21919255 - 2⁵ = 21919223 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21919255.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21919259) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 115270 + ... + 115459.

It is an arithmetic number, because the mean of its divisors is an integer number (3460950).

Almost surely, 2^21919255 is an apocalyptic number.

21919255 is a deficient number, since it is larger than the sum of its proper divisors (5768345).

21919255 is a wasteful number, since it uses less digits than its factorization.

21919255 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 230753.

The product of its digits is 8100, while the sum is 34.

The square root of 21919255 is about 4681.8004015549. The cubic root of 21919255 is about 279.8607087797.

The spelling of 21919255 in words is "twenty-one million, nine hundred nineteen thousand, two hundred fifty-five".