21541449 has 4 divisors (see below), whose sum is σ = 28721936. Its totient is φ = 14360964.

The previous prime is 21541447. The next prime is 21541451. The reversal of 21541449 is 94414512.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (21541447) and next prime (21541451).

It is not a de Polignac number, because 21541449 - 2¹ = 21541447 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21541447) 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, 3590239 + ... + 3590244.

It is an arithmetic number, because the mean of its divisors is an integer number (7180484).

Almost surely, 2^21541449 is an apocalyptic number.

It is an amenable number.

21541449 is a deficient number, since it is larger than the sum of its proper divisors (7180487).

21541449 is an equidigital number, since it uses as much as digits as its factorization.

21541449 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7180486.

The product of its digits is 5760, while the sum is 30.

The square root of 21541449 is about 4641.2766562660. The cubic root of 21541449 is about 278.2434637207.

It can be divided in two parts, 2 and 1541449, that added together give a palindrome (1541451).

The spelling of 21541449 in words is "twenty-one million, five hundred forty-one thousand, four hundred forty-nine".