21045489 has 8 divisors (see below), whose sum is σ = 28819200. Its totient is φ = 13651056.

The previous prime is 21045487. The next prime is 21045517. The reversal of 21045489 is 98454012.

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

It is not a de Polignac number, because 21045489 - 2¹ = 21045487 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21045481) 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, 94689 + ... + 94910.

It is an arithmetic number, because the mean of its divisors is an integer number (3602400).

Almost surely, 2^21045489 is an apocalyptic number.

It is an amenable number.

21045489 is a deficient number, since it is larger than the sum of its proper divisors (7773711).

21045489 is a wasteful number, since it uses less digits than its factorization.

21045489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 189639.

The product of its (nonzero) digits is 11520, while the sum is 33.

The square root of 21045489 is about 4587.5362668866. The cubic root of 21045489 is about 276.0914814370.

The spelling of 21045489 in words is "twenty-one million, forty-five thousand, four hundred eighty-nine".