21040895 has 4 divisors (see below), whose sum is σ = 25249080. Its totient is φ = 16832712.

The previous prime is 21040891. The next prime is 21040919. The reversal of 21040895 is 59804012.

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 21040895 - 2² = 21040891 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21040891) 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, 2104085 + ... + 2104094.

It is an arithmetic number, because the mean of its divisors is an integer number (6312270).

Almost surely, 2^21040895 is an apocalyptic number.

21040895 is a deficient number, since it is larger than the sum of its proper divisors (4208185).

21040895 is an equidigital number, since it uses as much as digits as its factorization.

21040895 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4208184.

The product of its (nonzero) digits is 2880, while the sum is 29.

The square root of 21040895 is about 4587.0355350706. The cubic root of 21040895 is about 276.0713907251.

The spelling of 21040895 in words is "twenty-one million, forty thousand, eight hundred ninety-five".