21449545 has 8 divisors (see below), whose sum is σ = 27719496. Its totient is φ = 15839616.

The previous prime is 21449539. The next prime is 21449599. The reversal of 21449545 is 54594412.

It can be written as a sum of positive squares in 4 ways, for example, as 3674889 + 17774656 = 1917^2 + 4216^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21449545 - 2²³ = 13060937 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21449545.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 164932 + ... + 165061.

It is an arithmetic number, because the mean of its divisors is an integer number (3464937).

Almost surely, 2^21449545 is an apocalyptic number.

It is an amenable number.

21449545 is a deficient number, since it is larger than the sum of its proper divisors (6269951).

21449545 is a wasteful number, since it uses less digits than its factorization.

21449545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 330011.

The product of its digits is 28800, while the sum is 34.

The square root of 21449545 is about 4631.3653494407. The cubic root of 21449545 is about 277.8472022326.

The spelling of 21449545 in words is "twenty-one million, four hundred forty-nine thousand, five hundred forty-five".