21768895 has 8 divisors (see below), whose sum is σ = 26170704. Its totient is φ = 17383104.

The previous prime is 21768893. The next prime is 21768911. The reversal of 21768895 is 59886712.

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 21768895 - 2¹ = 21768893 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21768893) 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, 774 + ... + 6643.

It is an arithmetic number, because the mean of its divisors is an integer number (3271338).

Almost surely, 2^21768895 is an apocalyptic number.

21768895 is a deficient number, since it is larger than the sum of its proper divisors (4401809).

21768895 is an equidigital number, since it uses as much as digits as its factorization.

21768895 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8009.

The product of its digits is 241920, while the sum is 46.

The square root of 21768895 is about 4665.7148434082. The cubic root of 21768895 is about 279.2193177098.

The spelling of 21768895 in words is "twenty-one million, seven hundred sixty-eight thousand, eight hundred ninety-five".