21448855 has 4 divisors (see below), whose sum is σ = 25738632. Its totient is φ = 17159080.

The previous prime is 21448841. The next prime is 21448859. The reversal of 21448855 is 55884412.

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

It is not a de Polignac number, because 21448855 - 2²³ = 13060247 is a prime.

It is a super-2 number, since 2×21448855² = 920106761622050, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21448859) 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, 2144881 + ... + 2144890.

It is an arithmetic number, because the mean of its divisors is an integer number (6434658).

Almost surely, 2^21448855 is an apocalyptic number.

21448855 is a deficient number, since it is larger than the sum of its proper divisors (4289777).

21448855 is an equidigital number, since it uses as much as digits as its factorization.

21448855 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4289776.

The product of its digits is 51200, while the sum is 37.

The square root of 21448855 is about 4631.2908567698. The cubic root of 21448855 is about 277.8442228901.

The spelling of 21448855 in words is "twenty-one million, four hundred forty-eight thousand, eight hundred fifty-five".