21897795 has 8 divisors (see below), whose sum is σ = 35036496. Its totient is φ = 11678816.

The previous prime is 21897781. The next prime is 21897797. The reversal of 21897795 is 59779812.

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 21897795 - 2⁵ = 21897763 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21897797) 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, 729912 + ... + 729941.

It is an arithmetic number, because the mean of its divisors is an integer number (4379562).

Almost surely, 2^21897795 is an apocalyptic number.

21897795 is a deficient number, since it is larger than the sum of its proper divisors (13138701).

21897795 is a wasteful number, since it uses less digits than its factorization.

21897795 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1459861.

The product of its digits is 317520, while the sum is 48.

The square root of 21897795 is about 4679.5079869576. The cubic root of 21897795 is about 279.7693466133.

The spelling of 21897795 in words is "twenty-one million, eight hundred ninety-seven thousand, seven hundred ninety-five".