21280853 has 8 divisors (see below), whose sum is σ = 23268000. Its totient is φ = 19302480.

The previous prime is 21280843. The next prime is 21280873. The reversal of 21280853 is 35808212.

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

It is a cyclic number.

It is not a de Polignac number, because 21280853 - 2⁶ = 21280789 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21280823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3551 + ... + 7427.

It is an arithmetic number, because the mean of its divisors is an integer number (2908500).

Almost surely, 2^21280853 is an apocalyptic number.

It is an amenable number.

21280853 is a deficient number, since it is larger than the sum of its proper divisors (1987147).

21280853 is a wasteful number, since it uses less digits than its factorization.

21280853 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4387.

The product of its (nonzero) digits is 3840, while the sum is 29.

The square root of 21280853 is about 4613.1174925423. The cubic root of 21280853 is about 277.1168990537.

The spelling of 21280853 in words is "twenty-one million, two hundred eighty thousand, eight hundred fifty-three".